Kill satan, get rich. Devilutionx is an excellent and highly portable free-software re-implementation of the diablo engine, with multiple quality of life and usability modifications, modding support, and multiplayer support. It runs on everything from Amigas to the Nintendo Switch. If you can't find it in your operating system's software repository you can build it. Lack of dedicated server means games must be arranged in #sqt.
Devilutionx requires the original asset files from Diablo and/or Hellfire expansion pack. You can find them here.