Games like Welcome to Kowloon
Games like Welcome to Kowloon include Outlast, Layers of Fear (2016), Mouthwashing, SOMA, and Outlast 2. We matched them by the tags players give Welcome to Kowloon on Steam (Horror, Atmospheric, Psychological Horror, Adventure, and Walking Simulator): closest matches first, and among equally close ones the better-known games.

Outlast
Shared: Horror · Atmospheric · Psychological Horror

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

Mouthwashing
Shared: Horror · Psychological Horror · Atmospheric

SOMA
Shared: Horror · Atmospheric · Psychological Horror

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

Still Wakes the Deep
Shared: Horror · Psychological Horror · Walking Simulator

Firewatch
Shared: Atmospheric · Adventure · Walking Simulator

Visage
Shared: Horror · Psychological Horror · Atmospheric

What Remains of Edith Finch
Shared: Atmospheric · Walking Simulator · First-Person

MiSide
Shared: Psychological Horror · Horror · Atmospheric

Poppy Playtime
Shared: Horror · First-Person · Psychological Horror

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

Blair Witch
Shared: Horror · Psychological Horror · Adventure

Little Nightmares II
Shared: Horror · Adventure · Atmospheric

Little Nightmares
Shared: Horror · Atmospheric · Adventure

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

From The Darkness
Shared: Horror · Psychological Horror · Dark

Scorn
Shared: Horror · Atmospheric · First-Person

Amnesia: A Machine For Pigs
Shared: Horror · Atmospheric · Walking Simulator

Resident Evil 7 Biohazard
Shared: Horror · First-Person · Atmospheric

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

The Beast Inside
Shared: Horror · Adventure · First-Person

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

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