Games like Five Signals
Games like Five Signals include Alan Wake, Outlast, Mouthwashing, Sally Face - Episode One, and Poppy Playtime. We matched them by the tags players give Five Signals on Steam (Action, Adventure, Horror, Psychological Horror, and Atmospheric): closest matches first, and among equally close ones the better-known games.

Alan Wake
Shared: Action · Horror · Adventure

Outlast
Shared: Horror · Psychological Horror · Atmospheric

Mouthwashing
Shared: Horror · Psychological Horror · Atmospheric

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

Poppy Playtime
Shared: Horror · Psychological Horror · Adventure

Phasmophobia
Shared: Horror · Psychological Horror · Supernatural

Darkwood
Shared: Horror · Adventure · Action

Little Nightmares II
Shared: Adventure · Horror · Atmospheric

SOMA
Shared: Horror · Psychological Horror · Atmospheric

Total Chaos
Shared: Action · Horror · Adventure

Amnesia: The Dark Descent
Shared: Horror · Psychological Horror · Atmospheric

Detention
Shared: Horror · Psychological Horror · Atmospheric

Fran Bow
Shared: Psychological Horror · Horror · Adventure

Little Nightmares
Shared: Horror · Adventure · Atmospheric

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

Firework
Shared: Horror · Psychological Horror · Atmospheric

Murdered: Soul Suspect
Shared: Adventure · Horror · Action

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

Outlast 2
Shared: Horror · Psychological Horror · Atmospheric

Alan Wake's American Nightmare
Shared: Action · Adventure · Horror

The Mortuary Assistant
Shared: Horror · Supernatural · Atmospheric

SILENT HILL f
Shared: Horror · Psychological Horror · Action

Notch - The Innocent LunA: Eclipsed SinnerS
Shared: Horror · Adventure · Psychological Horror

Hellblade: Senua's Sacrifice
Shared: Atmospheric · Adventure · Horror