Games like Hide Alone
Games like Hide Alone include Outlast, Poppy Playtime, Five Nights at Freddy's, Outlast 2, and Phasmophobia. We matched them by the tags players give Hide Alone on Steam (Horror, Indie, Dark, Psychological Horror, and Realistic): closest matches first, and among equally close ones the better-known games.

Outlast
Shared: Horror · Psychological Horror · Atmospheric

Poppy Playtime
Shared: Horror · Dark · Singleplayer

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

Outlast 2
Shared: Horror · Psychological Horror · Dark

Phasmophobia
Shared: Horror · Psychological Horror · Dark

Five Nights at Freddy's 2
Shared: Horror · Psychological Horror · Indie

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

Visage
Shared: Horror · Psychological Horror · Dark

Slender: The Arrival
Shared: Horror · Indie · Dark

SOMA
Shared: Horror · Psychological Horror · Dark

Little Nightmares
Shared: Horror · Dark · Atmospheric

The Outlast Trials
Shared: Horror · Psychological Horror · First-Person

Ultimate Custom Night
Shared: Horror · Singleplayer · Difficult

Mouthwashing
Shared: Horror · Psychological Horror · Indie

Little Nightmares II
Shared: Horror · Dark · Psychological Horror

Buckshot Roulette
Shared: Dark · Horror · Indie

Ready or Not
Shared: Realistic · Horror · Singleplayer

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

DEVOUR
Shared: Horror · Psychological Horror · Dark

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

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

Backrooms: Escape Together
Shared: Horror · Psychological Horror · Atmospheric

Five Nights at Freddy's 3
Shared: Horror · Psychological Horror · Indie

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