Revolt hasn’t added federation because it can be a major complexity increase in the codebase, but apparently they might be allowing instance owners to integrate polyproto support (polyproto is a work-in-progress federated chat system). If you want a discord like interface for Matrix, Cinny exists. I personally prefer revolt in some ways as Matrix feels like it doesn’t fit the use case for discord as well.
Factorio is pretty good, allows you to download any version of the game for any OS as many times as you want as long as you own the game (also allows downloading from site even if you bought from steam), doesn’t need internet connection to run, the multiplayer is player hosted (exception is authentication and optional blocklists)
There’s a web version you can use just fine