Games like Another Side
Games like Another Side include Poppy Playtime, What Remains of Edith Finch, MiSide, No, I'm not a Human, and SOMA. We matched them by the tags players give Another Side on Steam (Psychological Horror, Singleplayer, First-Person, Mystery, and Dark Fantasy): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Singleplayer · Horror · First-Person

What Remains of Edith Finch
Shared: Mystery · First-Person · Story Rich

MiSide
Shared: Psychological Horror · First-Person · Singleplayer

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

SOMA
Shared: Psychological Horror · Horror · Story Rich

Outer Wilds
Shared: Mystery · Exploration · Story Rich

Firewatch
Shared: Mystery · First-Person · Singleplayer

Sally Face - Episode One
Shared: Psychological Horror · Story Rich · Horror

Layers of Fear (2016)
Shared: Psychological Horror · Horror · First-Person

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

Five Nights at Freddy's: Security Breach
Shared: Singleplayer · Horror · First-Person

Amnesia: A Machine For Pigs
Shared: Psychological Horror · Horror · First-Person

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

Little Nightmares II
Shared: Singleplayer · Horror · Psychological Horror

Outlast
Shared: First-Person · Psychological Horror · Horror

Fran Bow
Shared: Psychological Horror · Horror · Story Rich

Mouthwashing
Shared: Psychological Horror · Horror · Story Rich

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

SILENT HILL 2
Shared: Psychological Horror · Horror · Story Rich

Escape the Backrooms
Shared: Psychological Horror · Horror · First-Person

Buckshot Roulette
Shared: First-Person · Singleplayer · Horror

Little Nightmares
Shared: Singleplayer · Horror · Psychological Horror

Inside the Backrooms
Shared: Psychological Horror · Horror · First-Person

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