Games like Sinister Remains
Games like Sinister Remains include Mouthwashing, Sally Face - Episode One, MiSide, Firewatch, and Fears to Fathom - Ironbark Lookout. We matched them by the tags players give Sinister Remains on Steam (Psychological Horror, Thriller, Horror, Adventure, and Atmospheric): closest matches first, and among equally close ones the better-known games.

Mouthwashing
Shared: Psychological Horror · Horror · Atmospheric

Sally Face - Episode One
Shared: Psychological Horror · Horror · Adventure

MiSide
Shared: Psychological Horror · Horror · Story Rich

Firewatch
Shared: Adventure · Atmospheric · Walking Simulator

Fears to Fathom - Ironbark Lookout
Shared: Psychological Horror · Horror · Thriller

Firework
Shared: Horror · Psychological Horror · Atmospheric

Summer of '58
Shared: Thriller · Horror · Psychological Horror

Layers of Fear (2016)
Shared: Psychological Horror · Horror · Atmospheric

Little Nightmares II
Shared: Horror · Adventure · Psychological Horror

What Remains of Edith Finch
Shared: Atmospheric · Walking Simulator · Adventure

Detention
Shared: Psychological Horror · Horror · Atmospheric

Alan Wake
Shared: Horror · Thriller · Adventure

Phasmophobia
Shared: Horror · Psychological Horror · Supernatural

SILENT HILL 2
Shared: Psychological Horror · Horror · Atmospheric

Fran Bow
Shared: Psychological Horror · Horror · Adventure

No, I'm not a Human
Shared: Psychological Horror · Horror · Atmospheric

SOMA
Shared: Psychological Horror · Horror · Atmospheric

Little Nightmares
Shared: Horror · Adventure · Atmospheric

Oxenfree
Shared: Atmospheric · Adventure · Supernatural

Raging Loop
Shared: Psychological Horror · Adventure · Psychological

The Painscreek Killings
Shared: Horror · Atmospheric · Detective

Poppy Playtime
Shared: Horror · Psychological Horror · Adventure

Amnesia: A Machine For Pigs
Shared: Horror · Psychological Horror · Atmospheric

Fears to Fathom - Norwood Hitchhike
Shared: Psychological Horror · Horror · Thriller