https://github.com/sonic2kk/steamtinkerlaunch for when you need MO2 or Nexus (that isn't Stardew). Keep in mind this will install a new instance of the app for each game you use it with (in its proton prefix folder).
https://github.com/Nexus-Mods/NexusMods.App is the current version of the new Nexus Mod Manager App, which has linux support. Currently it only has game support for Stardew Valley.
As many others have said, go with PrismLauncher for Minecraft. Modrinth's launcher works fine too, but doesn't have curseforge support.