ATOM RPG like other users said. A very faithful (sometimes too faithful tbh imo) spiritual successor to Fallout 1/2 except set in the USSR. I highly recommend it if you are into Fallout style CRPGs. As in, you can recruit followers but you don't directly control them in combat, charisma/speech can have a huge impact on how some conflicts are solved, you get Action Points to use every turn, overworld traveling with random encounters, cultural references and silly bits even to a detriment (just like Fallout!), etc.

It's the closest thing to a Fallout remake but in 3d and some (only some) modernizations.