The TVTropes Trope Finder is where you can come to ask questions like "Do we have this one?" and "What's the trope about...?" Trying to rediscover a long lost show or other medium but need a little help? Head to Media Finder and try your luck there. Want to propose a new trope? You should be over at the Trope Launch Pad.
It would probably be fair to say that "based on Werewolf/Mafia" is the closest thing to the name of the subgenre, for lack of anything more official. It's been around since 1986, and elements of that find-the-traitor style of gameplay have found their way into into larger board games like Shadows Over Camelot/Battlestar Galactica as well over the years, but as a party game, it's very informal.
Mafia
on The Other Wiki.
This is Ten Little Murder Victims.
Mafia and The Werewolves of Miller's Hollow are already listed. (Also noting a bit of Older Than They Think here: the Trope Codifiers are the Agatha Christie novel And Then There Were None and the interactive dinner-theater mystery games that it inspired.)
Edited by Scorpion451They fit the trope, definitely, but it's not the name of the genre, and there are enough clones of this to make for an index of their own. I did think about mentioning murder mystery parties, Assassin, and Clue, but I don't know how straight a line can be drawn between those and this. It's an idea that I think could easily arise independently in the latter-days USSR or when talking about The Mafiya.
Edited by Unsung

There a few recent games like Deceit or the Secret Neighbor Spin-Off of Hello Neighbor were players play as a group trying to complete tasks to escape but some players are secretly a monster trying to pick the others off one by one
Is there a name for this genre?
Edited by jormis29