Metro gives some similar atmospheric vibes in places, but is fundamentally a very different game. It's a much more linear experience, nowhere near as bad as the likes of something like COD granted. But it's a far cry from the open world nature of Stalker. There's very clearly defined areas and levels that you progress through, even if you have relative freedom to handle your encounters and approach. I really enjoyed all the Metro games, but it definitely does not scratch the same itch.
Survarium was made by ex-GSC employees, but it's been in early access for ages and is an online f2p shooter. And has rather mixed Steam reviews. It's probably not quite Stalker due to its online multiplayer nature. I haven't checked it out myself but it is free to play....
Chernobylite seems like another attempt at a Stalker-esque game. Also still in Early Access. Also haven't played it myself, but the Steam reviews are positive.