Games like Oversleep
Games like Oversleep include Portal, Portal 2, Zup! S, Zup!, and Zup! 2. We matched them by the tags players give Oversleep on Steam (Puzzle, 3D, First-Person, Relaxing, and Casual): closest matches first, and among equally close ones the better-known games.

Portal
Shared: Puzzle · First-Person · Sci-fi

Portal 2
Shared: Puzzle · First-Person · Singleplayer

Zup! S
Shared: Puzzle · Casual · Relaxing

Zup!
Shared: Puzzle · Casual · Relaxing

Zup! 2
Shared: Puzzle · Casual · Relaxing

LIMBO
Shared: Puzzle · Puzzle Platformer · Dark

Superliminal
Shared: Puzzle · First-Person · Physics

Zup! F
Shared: Puzzle · Casual · Relaxing

Monument Valley
Shared: Puzzle · Relaxing · Casual

Zup! X
Shared: Puzzle · Casual · Relaxing

Viewfinder
Shared: Puzzle · First-Person · Puzzle Platformer

Poppy Playtime
Shared: Puzzle · First-Person · Singleplayer

Sizeable
Shared: Puzzle · Casual · Relaxing

Zup! 3
Shared: Puzzle · Casual · Relaxing

Slime Rancher 2
Shared: Relaxing · First-Person · Singleplayer

Zup! 8
Shared: Puzzle · Casual · Relaxing

A Story About My Uncle
Shared: First-Person · Puzzle · Singleplayer

Hook
Shared: Puzzle · Casual · Relaxing

Donut County
Shared: Puzzle · Casual · Physics

Berry Bury Berry
Shared: 3D · First-Person · Physics

Zup! Z
Shared: Puzzle · Casual · Relaxing

PowerWash Simulator
Shared: Casual · Relaxing · First-Person

Antichamber
Shared: Puzzle · First-Person · Minimalist

Zup! 6
Shared: Puzzle · Casual · Relaxing