Games like s.p.l.i.t
Games like s.p.l.i.t include Poppy Playtime, No, I'm not a Human, MiSide, SOMA, and Little Nightmares II. We matched them by the tags players give s.p.l.i.t on Steam (Simulation, Hacking, Psychological Horror, Atmospheric, and Interactive Fiction): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Singleplayer · Psychological Horror · Horror

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

MiSide
Shared: Psychological Horror · Atmospheric · Singleplayer

SOMA
Shared: Psychological Horror · Atmospheric · Horror

Little Nightmares II
Shared: Atmospheric · Psychological Horror · Singleplayer

Pony Island
Shared: Psychological Horror · Hacking · Singleplayer

Little Nightmares
Shared: Atmospheric · Singleplayer · Horror

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

Welcome to the Game
Shared: Hacking · Simulation · Psychological Horror

Sally Face - Episode One
Shared: Psychological Horror · Atmospheric · Dark

Outlast
Shared: Atmospheric · Psychological Horror · Horror

Firework
Shared: Psychological Horror · Atmospheric · Horror

ROUTINE
Shared: Psychological Horror · Atmospheric · Singleplayer

Unheard - Voices of Crime
Shared: Short · Thriller · Simulation

Iron Lung
Shared: Psychological Horror · Atmospheric · Short

Welcome to the Game II
Shared: Hacking · Psychological Horror · Simulation

Hacknet
Shared: Simulation · Hacking · Typing

Cyber Manhunt
Shared: Simulation · Hacking · Singleplayer

Mouthwashing
Shared: Psychological Horror · Atmospheric · Horror

DEAD LETTER DEPT.
Shared: Simulation · Atmospheric · Psychological Horror

Garten of Banban
Shared: Psychological Horror · Singleplayer · Horror

Outlast 2
Shared: Psychological Horror · Atmospheric · Singleplayer

Tiny Bunny
Shared: Atmospheric · Psychological Horror · Horror

SIGNALIS
Shared: Psychological Horror · Atmospheric · Singleplayer