Games like September Fall - Loneliness
Games like September Fall - Loneliness include Escape the Backrooms, Outlast, Five Nights at Freddy's: Security Breach, The Beast Inside, and Poppy Playtime. We matched them by the tags players give September Fall - Loneliness on Steam (Horror, Action, Adventure, Psychological Horror, and Survival Horror): closest matches first, and among equally close ones the better-known games.

Escape the Backrooms
Shared: Horror · Psychological Horror · Survival Horror

Outlast
Shared: Horror · Survival Horror · Psychological Horror

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

The Beast Inside
Shared: Horror · Adventure · Action

Poppy Playtime
Shared: Horror · Singleplayer · Survival Horror

Resident Evil Requiem
Shared: Horror · Survival Horror · Action

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

Lethal Company
Shared: Horror · Survival Horror · First-Person

Resident Evil Village
Shared: Horror · Survival Horror · Action

SILENT HILL: Townfall
Shared: Horror · Action · Adventure

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

The Forest
Shared: Horror · Adventure · Action

Five Nights at Freddy's: Secret of the Mimic
Shared: Horror · Adventure · Action

Outlast 2
Shared: Horror · Psychological Horror · Survival Horror

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

Darkwood
Shared: Horror · Adventure · Action

Dark Deception
Shared: Horror · Psychological Horror · Singleplayer

SOMA
Shared: Horror · Psychological Horror · Survival Horror

Garten of Banban
Shared: Horror · Psychological Horror · Singleplayer

Visage
Shared: Horror · Psychological Horror · Survival Horror

The Outlast Trials
Shared: Horror · Psychological Horror · Survival Horror

Spooky's Jump Scare Mansion: HD Renovation
Shared: Horror · Adventure · Action

Choo-Choo Charles
Shared: Horror · Survival Horror · Singleplayer

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