Games like Atonement
Games like Atonement include Ready or Not, METRO 2033 Redux, Metro Exodus, METRO Last Light Redux, and Half-Life 2. We matched them by the tags players give Atonement on Steam (FPS, Singleplayer, Atmospheric, Horror, and Thriller): closest matches first, and among equally close ones the better-known games.

Ready or Not
Shared: FPS · Singleplayer · Realistic

METRO 2033 Redux
Shared: FPS · Atmospheric · Horror

Metro Exodus
Shared: FPS · Singleplayer · Atmospheric

METRO Last Light Redux
Shared: FPS · Atmospheric · Singleplayer

Half-Life 2
Shared: FPS · Singleplayer · Atmospheric

Black Mesa
Shared: FPS · Singleplayer · Atmospheric

Half-Life: Alyx
Shared: FPS · Horror · Singleplayer

BioShock™ Remastered
Shared: FPS · Atmospheric · Singleplayer

BioShock™
Shared: FPS · Atmospheric · Singleplayer

MiSide
Shared: Horror · Singleplayer · Atmospheric

Poppy Playtime
Shared: Singleplayer · Horror · Puzzle

Resident Evil Requiem
Shared: Horror · FPS · Singleplayer

Little Nightmares
Shared: Atmospheric · Horror · Singleplayer

Five Nights at Freddy's: Security Breach
Shared: Singleplayer · Horror · Multiple Endings

Little Nightmares II
Shared: Singleplayer · Horror · Atmospheric

Call of Duty®
Shared: FPS · Singleplayer · Action

BioShock Infinite
Shared: FPS · Singleplayer · Atmospheric

BioShock™ 2 Remastered
Shared: FPS · Singleplayer · Atmospheric

BioShock® 2
Shared: FPS · Singleplayer · Atmospheric

Resident Evil Village
Shared: Singleplayer · Horror · FPS

INSIDE
Shared: Atmospheric · Horror · Singleplayer

S.T.A.L.K.E.R. 2: Heart of Chornobyl - Standard Edition
Shared: FPS · Atmospheric · Singleplayer

Resident Evil 7 Biohazard
Shared: Horror · Singleplayer · Atmospheric

No, I'm not a Human
Shared: Horror · Singleplayer · Indie