Darkwood. https://www.gog.com/en/game/darkwood

Signalis.

No, I'm not Human is a great little game.

Mouthwashing

Water Womb World is free on Steam. It's short but it's really something.

Iron Lung. Very clever premise. Deeply, intensely creepy throughout.

No one lives under the lighthouse

I'm not much of a horror game player, but I enjoyed this one (especially the graphics)

Lethal Company

• SOMA
• Amnesia: The Dark Descent

Dredge is like cozy cosmic horror. Great game.

I'd recommend Crow Country. It's very old school resident evil/silent hill influenced. Not the longest game, but very worth your time. https://store.steampowered.com/app/1996010/Crow_Country/

little nightmares 1-3, reanimal

Faith: The Unholy Trinity

It's an 8-bit horror game. Not sure if this is what you are looking for. I definitely recommend it if you are not put off by 8-bit graphics.

Receiver 2 in my opinion. Not exactly horror but I still have flashbacks from the activation Beep from kill drones. Mechanically tricky to learn though.

I love Envelope. It's a weird mystery story in an open-world little town, where you're mysteriously given an ominous mission and there are many ways to try to achieve it, and many ways to fail. It's super fun.

Lost in Vivo's one that hasn't been mentioned yet, so I'll pick that one. Your mission is to find your lost service dog that got flushed down a storm drain

no nsfw plz

I have not played it but I have seen a lot of gameplay of it, Voices of the void might be worth checking.