the subscription is per user, yes.
i haven’t tried those games specifically, but in theory they should work.
have a look at this thread Plex Arcade - Working Core Tracker which lists the platforms and cores which are working well. we don’t have support (yet, at least) for C64 or Amiga.
Fairly light (a few MBps), depends on game of course.
It’s part of the media server.
Only macOS and Windows servers at the moment.
