It's an old boomer MMO, but it's free. I currently play on a server that uses the SWGEMU project, but there are other servers that use their own custom codebase/launcher
If you want to start you can check out https://www.reddit.com/r/swg/ which has information on how to get the game up and running.
Some of the popular servers are
SWG: Legends
SWG: Restoration III
SWG: Sunrunner II
SWG: Empire in Flames
SWG: Finalizer
I currently play on Sunrunner II which is a smaller community of about 100-200 players, as opposed to legends which has about a 1000 give or take
https://swgsunrunner2.com/