In nWoD? I imagine not much and kept away from most important magic. At least in oWoD you can change their consensus, no such luck in nWoD.
I mean... technically you can change their consensus.
It just literally causes them mental trauma to do so.
3 failed Integrity tests caused by exposure to magic and you become a sleepwalker.
but they should at least be aware of each other and the the different factions that exist within each group.
It has always been played up, in literally every game circle, that supernatural groups are aware that there are others out there.
In the old fanclub LARPS you, for the most part, just ignored them politely due to the paperwork for getting 2 venues to crossover for even a single night being a pain in the ass.
At the table, as others have said, you adjust it to match the game and tone you want and what mechanical ness you want at the table.
Many games I've known of have had someone do something with other supernaturals, sometimes to the point that it can warp the game somewhat due to having to come up with stuff for that person(s) with regards to whatever they're dealing with. Like, say, having to come up with Werewolf plots that are going on because a vampire managed to somehow get in good with one of the local packs.
As an example, in the game I'm currently running each city has a tendency for one big supreme power block of supernaturals to form with only the largest cities in a region likely to see multiple power blocks. The only ones that ignore this rule are mages, who are actively encouraged by their peer mages by other mages to project a somewhat united front to other supernaturals, codifying that there are 3 kinds of mage. The Pentacle, the Seekers/Exarchs, and the Insane. Pentacle portray themselves as ancient and powerful inheritors of Atlantis, which is totesmagotes a place but you'll never see it because it didn't sink it ascended, and is where the most powerful Archmaster reality warping types live, so don't mess with us. The Pentacle's portrayal of the Seekers of the Throne / Exarchs is as pretenders to the throne who started an ancient war that saw their own homeland and that of several others destroyed. As such the Exarchs stole off into the Supernal and caused a lot of damage to reality and are still actively playing at reality terrorist, but the more they've exerted direct power the more they've chained themselves and limited how they can apply that power, which is why they work through Seers now. Seers are mostly described as being either crazy or duped, and depending on the age of the Pentacle you ask you'll get lots of allegories to stuff like Nazi Germany, the various powers in WW1 who would send their men charging into no man's land for basically no good reason, Communists states during the cold war, with some more modern ones likening them to ISIS/ISIL. Pentacles describe any mage that isn't actively 'with' the Pentacle or a Seeker as being one of 'the mad' or 'the insane' or any number of other words and basically actively spread that they're dangerously insane lone wolf types, with agents of the Guardians and Arrows in particular being notable for often times paying for info on these "dangerous rogue elements".
The Seekers of the Throne on the other hand portray themselves as the winners of an ancient conflict and the servants of the rightful rulers of all of reality who are in the process of slowly purging the last sparks of the ancient and fallen Atlantis which they definitely destroyed. As a supernatural if you get caught up in their web you generally have 3 outcomes. First they don't care about you, second they do so you had better bend knee and serve, third if you don't then they'll destroy you. Seekers also tend to pay for information on the "Insane" though they don't actively comment on them being dangerous, with some seekers actively dropping hints that these supposed 'rogues' are actually their own agents. Which from a meta standpoint is 100% BS, but the Seekers have need to BS that they're in total control. As for the Pentacle, the Seekers call them enemy combatants fighting a war that's already been won, with their own allegories being paintings of some modern conflicts with groups that hide out in remote places waging wars long after the war is already over because they refuse to accept that it's over. Hiroo Onoda is a good example off the top of my head, but generally speaking the Seekers try to play off the conflicts as necessary but decidedly tragic and how it would all just end if the Pentacle would just accept the war was over and rejoin society and stop rocking the boat that is reality.
Lone wolf types, aka 'the insane', are to varied to pin down.
But yeah. Various groups form their own blocks of power, many of which might overlap, and it just kind of depends on the area whether 2 groups actively work together or avoid one another or what. The biggest issues with working in a group is being pulled in different directions, which is also exacerbated by things like Mages moving around somewhat freely and generally ignoring any powers in an area that aren't other Mages, werewolves being able to jump into the Shadow with few being able to follow, and Changelings being able to do much the same with the Hedge. Which leaves vampires as kind of an odd duck out as they run around in purely mortal circles and don't have the same kind of travel gumption.
I have a tendency to not incorporate God Machine Demon stuff or Promethean or Beast or Mummy or Geist. God Machine because their stuff tends to warp everything around it due to the scale of things. Mummy because why does this even exist? Promethean because while the game has a neat concept, anything that's going to basically slowly destroy the world in a decently visible way just by existing is going to have been squashed by the Mages at some point. Geist because it only got 1 book in the past and its powers are kind of insane at times. And finally I'm not going to talk about
Abuser: The You Had It Coming Beast.
But yeah, as others have said, there's no benefit to writing all splats as beholden to another splat in their own book. Also we have a unifying version that built the entire world around concepts that all of the things exist at once. It's called Monty Cook's World of Darkness and there's a reason no one ever talks about it, and that reason for those of you who can't read subtlety in text is that it's pretty awful and is WoD: D20 Modern (Sort of) Edition. Because that's just what WoD needed! An edition where everyone is a different class and we all roll like it's D&D up in here!
