Games like Zone 404
Games like Zone 404 include Metro Exodus, METRO 2033 Redux, METRO Last Light Redux, Fallout 4, and S.T.A.L.K.E.R. 2: Heart of Chornobyl - Standard Edition. We matched them by the tags players give Zone 404 on Steam (Horror, Atmospheric, Post-apocalyptic, First-Person, and Hidden Object): closest matches first, and among equally close ones the better-known games.

Metro Exodus
Shared: Post-apocalyptic · Atmospheric · Horror

METRO 2033 Redux
Shared: Post-apocalyptic · Atmospheric · Horror

METRO Last Light Redux
Shared: Post-apocalyptic · Atmospheric · Horror

Fallout 4
Shared: Post-apocalyptic · Atmospheric · Exploration

S.T.A.L.K.E.R. 2: Heart of Chornobyl - Standard Edition
Shared: Post-apocalyptic · Atmospheric · Exploration

Half-Life: Alyx
Shared: Horror · Female Protagonist · First-Person

Resident Evil Requiem
Shared: Horror · First-Person · Singleplayer

Outlast
Shared: Horror · Atmospheric · First-Person

Ready or Not
Shared: Horror · Realistic · First-Person

Resident Evil 7 Biohazard
Shared: Horror · First-Person · Atmospheric

Resident Evil Village
Shared: Horror · First-Person · Singleplayer

BioShock™ Remastered
Shared: Atmospheric · Horror · First-Person

Fallout: New Vegas
Shared: Post-apocalyptic · First-Person · Exploration

SOMA
Shared: Horror · Atmospheric · First-Person

Poppy Playtime
Shared: Horror · First-Person · Singleplayer

What Remains of Edith Finch
Shared: Atmospheric · First-Person · Exploration

The Forest
Shared: Horror · First-Person · Exploration

Lethal Company
Shared: Horror · First-Person · Exploration

Alien: Isolation
Shared: Horror · Atmospheric · First-Person

Black Mesa
Shared: First-Person · Atmospheric · Singleplayer

BioShock™
Shared: Atmospheric · Horror · First-Person

Hellblade: Senua's Sacrifice
Shared: Atmospheric · Female Protagonist · Horror

Outlast 2
Shared: Horror · First-Person · Atmospheric

Five Nights at Freddy's: Security Breach
Shared: Horror · First-Person · Singleplayer