Games like Restless Nights
Games like Restless Nights include Poppy Playtime, Outlast, Resident Evil Village, Bendy and the Ink Machine, and Resident Evil 7 Biohazard. We matched them by the tags players give Restless Nights on Steam (Horror, Action, Survival Horror, Supernatural, and Atmospheric): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Horror · Singleplayer · Survival Horror

Outlast
Shared: Horror · Survival Horror · Atmospheric

Resident Evil Village
Shared: Horror · Survival Horror · Action

Bendy and the Ink Machine
Shared: Horror · Singleplayer · First-Person

Resident Evil 7 Biohazard
Shared: Horror · Survival Horror · Singleplayer

Bendy and the Dark Revival
Shared: Horror · Action · Survival Horror

Outlast 2
Shared: Horror · Survival Horror · First-Person

Five Nights at Freddy's
Shared: Horror · Survival Horror · Singleplayer

Garten of Banban
Shared: Horror · Singleplayer · First-Person

SOMA
Shared: Horror · Atmospheric · Survival Horror

Resident Evil 2
Shared: Horror · Survival Horror · Singleplayer

Slender: The Arrival
Shared: Horror · Survival Horror · First-Person

Resident Evil 4
Shared: Horror · Action · Survival Horror

Five Nights at Freddy's: Sister Location
Shared: Horror · Survival Horror · Singleplayer

Ultimate Custom Night
Shared: Horror · Survival Horror · Singleplayer

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

Resident Evil Requiem
Shared: Horror · Survival Horror · Action

Garten of Banban 2
Shared: Horror · Singleplayer · First-Person

Among the Sleep - Enhanced Edition
Shared: Horror · Atmospheric · Singleplayer

FIVE NIGHTS AT FREDDY'S: HELP WANTED
Shared: Horror · Survival Horror · Singleplayer

Five Nights at Freddy's 2
Shared: Horror · Survival Horror · Singleplayer

Five Nights at Freddy's 4
Shared: Horror · Survival Horror · Singleplayer

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

METRO 2033 Redux
Shared: Horror · Atmospheric · Action