I was going to say replaying but I feel like that limits the question to games like Prey or Fallout New Vegas that have endings and games like The Sims 2 or Cities Skylines where you can play indefinitely end up excluded.
I’m not really referring to games like League of Legends where you’re coming back every month. More so games where you stop playing for an extended period of time.
You have to have the original game files either from the disk or downloaded from GoG or steam. Then you need tes3mp which runs great on linux and windows. I personally play on a server called neravarine prophecies, they have seasonal events and the community is a lot of fun. It uses the same engine as openMW so most of the mods that work on OpenMW are compatible, I’d stick with cosmetics to keep the servers you join compatible.
Different servers have different rules, many of them forbid going into areas that cause server crashes, i.e. mornhould.
I had a blast, then I got my kids to play and i was there to guide them a bit when the game gets tough.