Of all things, the S.T.A.L.K.E.R. fan games (ones that have been made in forks of the engine, like Call of Chernobyl and Anomaly) have become some of my comfiest games.
There's something very enchanting about wandering through deceptively innocent-looking countryside and derelict farmhouses early in the game, and eventually progressing into more metropolitan and deadly places like Dead City, or the maps set in and around Pripyat. If you REALLY want a chill experience, you can turn down spawn rates in any of the versions that use STALKER Anomaly as their base, to make coming across other people or mutants rarer or basically non-existent if you want.
It's got so comfy for me, I've started getting into STALKER GAMMA, which (unless you disable some things on your own) forces you to engage more often with immersion-encouraging mechanics, like actually hunting and cooking mutant meat to keep food costs down, scavenging and repairing all the intricate parts of weapons and armours since you can't simply buy them anymore, and better planning and routing since by default in GAMMA you can only manually save at lit campfires (personally I have that disabled, but only because I ALREADY forget to save for half an hour or longer sometimes as it is).
