I think fighting games would make a good community, maybe with friendly tournaments organized regularly. The free ones that i know of are the hololive one (idol showdown) from steam and the emulated arcade titles from fightcade.

Monster hunter world. I bought it to have a replacement for genshin and it worked a little too well. It just feels different from any other game for how many things it does so well: from enemies to armor design to music to mechanics to weapon variety, everything is amazing.

Risk of rain 2, frostpunk.