Games like Sinisomnia
Games like Sinisomnia include Buckshot Roulette, Fran Bow, Sally Face - Episode One, Demonologist, and Detention. We matched them by the tags players give Sinisomnia on Steam (Strategy, Adventure, Indie, Simulation, and Horror): closest matches first, and among equally close ones the better-known games.

Buckshot Roulette
Shared: Strategy · Horror · Dark

Fran Bow
Shared: Adventure · Psychological Horror · Horror

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

Demonologist
Shared: Horror · Psychological Horror · Dark

Detention
Shared: Indie · Horror · Adventure

The Cat Lady
Shared: Adventure · Horror · Indie

Phasmophobia
Shared: Horror · Psychological Horror · Dark

Mouthwashing
Shared: Horror · Psychological Horror · Indie

Endacopia
Shared: Adventure · Horror · Psychological Horror

[Chillas Art] The Convenience Store
Shared: Indie · Adventure · Horror

Blair Witch
Shared: Adventure · Horror · Indie

Little Nightmares II
Shared: Adventure · Horror · Dark

The White Door
Shared: Adventure · Indie · Psychological Horror

Rusty Lake Paradise
Shared: Indie · Adventure · Horror

Little Nightmares
Shared: Adventure · Horror · Indie

CloverPit
Shared: Strategy · Psychological Horror · Horror

[Chillas Art] Stigmatized Property
Shared: Indie · Adventure · Horror

Five Nights at Freddy's
Shared: Horror · Indie · Psychological Horror

Little Misfortune
Shared: Indie · Adventure · Psychological Horror

Inscryption
Shared: Horror · Strategy · Dark

DISTRAINT: Deluxe Edition
Shared: Indie · Horror · Adventure

Cube Escape Collection
Shared: Horror · Indie · Psychological Horror

Poppy Playtime
Shared: Horror · Psychological Horror · Dark

Servant of the Lake
Shared: Adventure · Indie · Psychological Horror