Games like Project Exo
Games like Project Exo include Portal 2, LIMBO, Portal, COCOON, and A Story About My Uncle. We matched them by the tags players give Project Exo on Steam (Strategy, Adventure, Platformer, Puzzle, and Precision Platformer): closest matches first, and among equally close ones the better-known games.

Portal 2
Shared: Platformer · Puzzle · First-Person

LIMBO
Shared: Platformer · Puzzle · Puzzle Platformer

Portal
Shared: Puzzle · Puzzle Platformer · First-Person

COCOON
Shared: Adventure · Puzzle · Puzzle Platformer

A Story About My Uncle
Shared: Adventure · Platformer · First-Person

Polarity
Shared: Puzzle · Adventure · Strategy

Little Nightmares
Shared: Adventure · Puzzle Platformer · Puzzle

Viewfinder
Shared: Puzzle · Puzzle Platformer · Adventure

Moonleap
Shared: Platformer · Puzzle · Puzzle Platformer

Celeste
Shared: Precision Platformer · Platformer · Adventure

Q.U.B.E: Director's Cut
Shared: Puzzle · Adventure · First-Person

FEZ
Shared: Platformer · Puzzle · Adventure

Out There Somewhere
Shared: Platformer · Adventure · Puzzle

Antichamber
Shared: Puzzle · First-Person · Adventure

Defy Gravity Extended
Shared: Platformer · Puzzle Platformer · Puzzle

BEEP
Shared: Adventure · Platformer · Puzzle

Refunct
Shared: Platformer · Puzzle Platformer · First-Person

The Ball
Shared: Strategy · Puzzle · Puzzle Platformer

The Unfinished Swan
Shared: Adventure · Puzzle · Puzzle Platformer

Supraland
Shared: Adventure · Puzzle Platformer · Puzzle

Little Nightmares II
Shared: Adventure · Puzzle · Puzzle Platformer

Seen
Shared: Adventure · Puzzle · Platformer

ANIMAL WELL
Shared: Puzzle · Platformer · Puzzle Platformer

gravilon
Shared: Platformer · Puzzle · Adventure