The default experience of Vampire the Masquerade V5 is present day - that is, the 2020s. The tidal wave of Lore has moved forward - clans have shifted and changes, things have happened since previous versions set in earlier decades. The books lay out the Clans and the Sects as they exist now, which is fantastic if you want to play that default experience, but what if you want to play in an earlier time period?
You could solve this problem in a few ways. There are third party add-ons that have some of this information. One of these is In Darker Ages - https://www.storytellersvault.com/en/product/394339/in-darker-ages - this seems to cover the needed material. Another option would be to get the old books, look at the timelines and try to cobble something together.
This is intended to be another option. I'm going to slide back down the timeline and try to mention some changes that would need to happen to run in a game before a specific time. It will absolutely not be complete, conclusive, or definitive. I will suggest alternate banes for Clans, note changes to Sects, hit the high points of major Lore changes, which will hopefully provide enough information for a Grunge 90s, a Punk 80s, a Hippy 60s, a Flapper 20s, or a Victorian 1800s Chronicle from a mechanical point of view.
I'm going from present day back to the 1800s - if you want to go earlier than that, there's some fantastic third party work in the Storyteller's Vault.
Alternate Banes presented here are my work, based on the previous editions and my understanding of the intended flavour combined with modern sensibilities and intended to be mechanically compatible with V5. They are not in any way official.
Read this timeline from the top down to the year/decade you want to set your game, adjusting the rules/sects/banes as you pass each milestone.
2026
Current day in the Vampire the Masquerade V5 Canon. Everything is as it is in the V5 Source Books.
2020-2021
In 2020-2021, the Death Clans (Giovanni, Cappadocians, Samedi, Harbingers of Skulls, Nagaraja, and Lamiae) experience the Family Reunion and become the Hecata as a single Clan. Prior to this point, the different Death Clans had different Banes. There's a lot of details on the Family Reunion in the V5 book Cult of the Blood Gods. The non-Giovanni Death Clans may be difficult to play prior to this year, due to difficult Banes. In addition, the Giovanni are at war with most of the other Death Clans, especially the Cappadocians (whom they have driven near extinction) and most of the other Death Clans are rare throughout the United States, Canada, and Europe.
Giovanni
In the Family Reunion, all the Death Clans received the Giovanni curse of Excruciating Bite. Giovanni should just continue to use the Hecata V5 Clan Bane.
Cappadocians
Corpse-Like - The Cappadocians develop a Corpse-like appearance, with ashen pallor. They take their Bane Severity penalty to all social rolls with mortals.
Samedi
Decaying - The Samedi is a rotting zombie, with its flesh soft, sloughing off, and disgusting. All Samedi have the Repulsive Flaw (-2), can never improve their appearance, and in bright light can be a Masquerade violation.
Harbingers of Skulls
Desiccated - The Harbinger is a withered mummy like figure. All Harbingers have the Repulsive Flaw (-2), can never improve their appearance, and in bright light can be a Masquerade violation.
Nagaraja
Flesh-Eater - All Nagaraja have the Organovore Flaw (-2). They must consume human flesh with their blood in order to feed.
Lamiae
Plague-Bearer - Lamiae are deeply connected with the Dark Mother and bear a toxic curse from her. All Mortals fed on by Lamiae fall ill with the plague and are likely to die without modern medical intervention, losing one point of physical attribute per day until they die. Kindred who feed on Lamiae become also become a plague bearer until their Hunger increases to 5.
2019
Two very significant events happen in 2019. First, the Vermillion Wedding, where Victoria Ashe (a Camarilla Toreador) married Tegyrius (a Banu Haqim). This Blood Marriage - and their Blood Bonds to each other - sealed the deal that brought the Banu Haqim fully into the Camarilla. Before 2019, the Banu Haqim were Independent, mistrusted by the Camarilla, and had a reputation as mercenary to many non-Banu Haqim.
Also in 2019, the Lasombra Clan are in the Sabbat. Their leaders, the Amici Noctis, decide that the Sabbat will not survive the generational war with the Elders, Methuselahs and even older vampires that the Sabbat has engaged in. The Sabbat are fully wrapped up in the Gehenna Wars, this ancient war that suddenly has fresh intensity and the Lasombra want out. They make a bargain with the Camarilla in Chicago, sacrificing one Sabbat Elder of the Lasombra for each one allowed to join the Camarilla. Before this date, the Lasombra were one of the principal clans of the Sabbat and enemies of the Camarilla.
2014
In 2014, The Beckoning, the call that Elder vampires feel to go fight in the ancient conflicts of vampires, starts to be truly noticeable. This is the year some significant Princes disappear - Quintin of Boston, Calebros of New York to name two. The Beckoning seems to have started some years before, but before 2014, you can assume that most major cities will have major players, including Princes, that are Elders or even Methuselahs. After 2014, those powerhouses have largely left or faded away, leaving more space for young upstarts.
2013
Both the Followers of Set (the Ministry) and the Banu Haqim begin conversations with the Camarilla about joining. The Ministry are mid-negotiation in a Paris hotel when the hotel is firebombed, which causes the negotiations to collapse in ill-feelings and accusations. The Ministry officials rebrands - from The Followers of Set to the Ministry and the Clan starts to lean towards the Anarch movement and their cities. Prior to this date, the Ministry should be known as the Followers of Set and should be fully Independent.
2012
At a major Camarilla Convention called the Conclave of Prague, Brujah Theo Bell assassinates the Ventrue Hardestadt. Both of these Kindred were towering figures in their clans, so this is a monumental earthquake. Theo Bell declares the Brujah are no longer part of the Camarilla, and many of his clan follow him to the Anarchs. The Camarilla declares that all Kindred not aligned with them are enemies, ending the normal practice of tolerating Independents and Anarchs witLhin their city. Prior to this date, the Brujah should be major members of the Camarilla and most Camarilla Courts will tolerate openly Anarch or Independent members, provided they follow the Traditions.
2008
In 2008, a major Second Inquisition operation destroys the Tremere Prime Chantry in Vienna. All of the Council of Seven, the leaders of the Tremere, are believed to be killed in this event and the Pyramid, the network of Blood Bonds holding the Clan loyal to its leaders, is destroyed. Before this point, Tremere are part of this Pyramid of Blood Bonds, tying Childe to Sire all the way up to the Council of Seven. Until the Vienna Chantry's destruction, the Tremere are amongst the most disciplined and unified of clans, so prior to 2008, the Tremere have a different Bane and are much more cohesive.
Tremere
Hierarchical - All Tremere are forced to drink of the blood of the elders as they are accepted into the Clan. Tremere take one fewer drink to be bonded to a Tremere of lower Generation and take a two dice penalty to any attempt to resist Dominate from a lower Generation Tremere.
2007
The V5 Lasombra Bane involves touch screens, voice recognition, and technology. This year (which happens to be when the Apple iPhone came out) is a potentially a good point to switch Lasombra banes to something more impactful in earlier years. Consider this an alternate Bane.
Lasombra
Shadowy - Lasombra are creatures of Shadow and deny light. Their image does not reflect in mirrors and they take an additional Aggravated damage when exposed to sunlight.
2008
Night of Ashes - the Second Inquisition burns the Sabbat out of Montreal. In V5, the Sabbat are an antagonist Sect, scattered, focussed on the Gehenna Wars. But prior to 2008, the Sabbat acted as a Sect much like the Anarchs and the Camarilla in V5 - holding territory, having internal politics, having a certain level of stability.
2005
By 2005, the echoes of the Week of Nightmares cause the Sabbat to begin migrate to join the Gehenna Wars, starting the weakening of their cities and holdings.
2004
The major event of 2004 is the Fall of SchreckNet. SchreckNet was an encrypted network that the Nosferatu ran and maintained to provide secure communications for the Camarilla and other Kindred. They stored many secrets and boons on SchreckNet, so when the Second Inquisition broke its encryption and raided its servers, a great deal of information about Vampires, the Sects, and individuals were taken. The Second Inquisition leveraged this to attack Kindred both directly and indirectly, leading a great deal of damage and panic. This event lead to the Camarilla banning the use of technology to store or transmit Kindred secrets, and also caused the Nosferatu to lose resources, prestige, and secrrts. Prior to this time, influential Kindred had access to SchreckNet and the Nosferatu - while repugnant - were hugely important and held secrets over powerful Kindred in their cities.
1999
1999 was an incredibly turbulent year for Kindred. The most significant event was the Week of Nightmares, where Zapathasura, the Antediluvian - the Ancient Founder - of the Ravnos Clan awoke from his slumber and engages in battle with his ancient enemies. In the course of this week long battle, many powerful Ravnos Kindred were drawn in and consumed by their founder. The battle ends with Zapathasura destroyed by nuclear weapons and orbital space lasers. During and after the battle, all members of clan Ravnos go insane and go into a killing frenzy. When the week ends, there are few left. Prior to the Week of Nightmares, the Ravnos were more common and had a different Bane, since their current Bane is related to the death of their founder.
Ravnos
Hubris - The Ravnos are obsessed with pushing their luck, bargaining with Fate, and rolling the dice. If given two options - a safe path and a risky but flamboyant path - the Ravnos must take the risky path or suffer a penalty on their dice rolls equal to their Bane Severity until the end of the scene or until they choose the path of derring-do.
Arguably, the Week of Nightmares also started the increase in the number of Thin Bloods. Prior to 1999, Thin Bloods should be very rare, misunderstood, and mistrusted.
In 1999, the Gangrel Xavier encountered and was nearly slain by an ancient beast - potentially an Antediluvian or Methuselah of great power. He confronted the Camarilla and demanded that they acknowledge the danger of the ancients - and they ignored him. He declared the Camarilla to have been built on lies and took the Clan Gangrel out of the Camarilla, making it Independent. Prior to 1999, the Camarilla absolutely deny the existence of the Antediluvians and ancient Kindred and deny the risk they pose. Prior to 1999, the Gangrel were members of the Camarilla and were among their warriors, with the Brujah.
In 1999, the Harbingers of Skulls returned to the world from the Shadowlands. Prior to 1999, there were no Harbingers of Skulls around.
In 1999, as a result of the Week of Nightmares, the Sabbat Elders declared the Gehenna Wars.
1998
For the Banu Haqim, 1998 is an incredibly important year, because an ancient Banu Haqim awakes - Ur-Shulgi. He pushes the clan back towards the worship of Haqim, the clan founder. The clan splits - with some following Ur-Shulgi, others turning more towards the Camarilla. Prior to 1998, the Clan was more insular, focussed inward and had a Bane imposed on them by the Tremere. Ur-Shulgi broke that curse upon his awakening.
Banu Haqim
Blood-Cursed - The Banu Haqim are cursed by the Tremere to be unable to consume Vitae. A Banu Haqim that consumes Vampire Blood takes one Aggravated Damage per Hunger Slaked.
1944
In 1944, the Second Anarch Revolt kicked off, with the Brujah Jeremy MacNeil leading the uprising in Southern California. This Revolt lead to the Anarch Free States - before 1944, there were no Anarch cities or territories. The Barons of the Free States defined how an Anarch City could function.
1800
In 1800, the base state is that the Camarilla is the centre of the Kindred world, with the Sabbat as their antagonists and rivals. The 1800s for the Camarilla are the peak of its global power, riding along with the British and their industrial revolution.