Project Winter is somewhat similar, in that there are up to 2 "imposters", and the rest of the players have to accomplish some goal, but it has far more roles, different methods of killing for the traitors, methods of defending yourself, and it works on a proximity based voice chat system. One of the go-to recommendations for games similar to Among Us.
I've also heard that Unfortunate Space Men is similar too, but I can't really confirm that one. Besides that, you may need to search for boardgames, as Among Us is pretty much a boardgame in video game form, so TableTop Simulator might work out for you.