Games like Quadrant
Games like Quadrant include Alien: Isolation, Lethal Company, Outlast, SOMA, and Little Nightmares. We matched them by the tags players give Quadrant on Steam (Indie, Horror, Sci-fi, Survival Horror, and Stealth): closest matches first, and among equally close ones the better-known games.

Alien: Isolation
Shared: Horror · Sci-fi · Survival Horror

Lethal Company
Shared: Horror · Survival Horror · Sci-fi

Outlast
Shared: Horror · Survival Horror · Atmospheric

SOMA
Shared: Horror · Sci-fi · Atmospheric

Little Nightmares
Shared: Horror · Atmospheric · Indie

The Outlast Trials
Shared: Horror · Survival Horror · Stealth

Amnesia: The Bunker
Shared: Horror · Survival Horror · Atmospheric

Dead Space
Shared: Horror · Survival Horror · Sci-fi

Dead by Daylight
Shared: Horror · Survival Horror · Stealth

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

Dead Space (2008)
Shared: Horror · Sci-fi · Survival Horror

CASE: Animatronics
Shared: Horror · Survival Horror · Indie

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

Species: Unknown
Shared: Horror · Survival Horror · Atmospheric

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

Granny Remake
Shared: Horror · Survival Horror · Indie

Nuclear Nightmare
Shared: Horror · Survival Horror · Atmospheric

ROUTINE
Shared: Sci-fi · Atmospheric · Horror

Penumbra Overture
Shared: Horror · Indie · Survival Horror

Inside the Backrooms
Shared: Horror · Survival Horror · Indie

Prey
Shared: Sci-fi · Horror · Atmospheric

PANICORE
Shared: Horror · Survival Horror · Stealth

Poppy Playtime
Shared: Horror · Survival Horror · Indie

Slender: The Arrival
Shared: Horror · Indie · Survival Horror