Games like OUTCLAW
Games like OUTCLAW include Portal 2, A Hat in Time, Supraland, Chained Together, and Tinykin. We matched them by the tags players give OUTCLAW on Steam (Exploration, 3D Platformer, Puzzle Platformer, Collectathon, and Creature Collector): closest matches first, and among equally close ones the better-known games.

Portal 2
Shared: Puzzle Platformer · Puzzle · 3D Platformer

A Hat in Time
Shared: 3D Platformer · Collectathon · Exploration

Supraland
Shared: Exploration · Puzzle Platformer · 3D Platformer

Chained Together
Shared: Puzzle Platformer · 3D Platformer · Platformer

Tinykin
Shared: 3D Platformer · Action-Adventure · Puzzle Platformer

Yooka-Laylee
Shared: 3D Platformer · Collectathon · Exploration

Yooka-Replaylee
Shared: Exploration · 3D Platformer · Collectathon

Portal
Shared: Puzzle Platformer · 3D Platformer · Puzzle

Trine 3: The Artifacts of Power
Shared: Puzzle Platformer · 3D Platformer · Action-Adventure

Sonic Frontiers
Shared: 3D Platformer · Exploration · Action-Adventure

ANIMAL WELL
Shared: Exploration · Puzzle Platformer · Puzzle

Pumpkin Jack
Shared: 3D Platformer · Collectathon · Adventure

Tomb Raider IV-VI Remastered
Shared: 3D Platformer · Exploration · Action-Adventure

Aniimo
Shared: Creature Collector · Exploration · Collectathon

Trine 2: Complete Story
Shared: Puzzle Platformer · Action-Adventure · Platformer

FEZ
Shared: Exploration · Puzzle · Platformer

STAR WARS Jedi: Fallen Order™
Shared: Action-Adventure · Exploration · Platformer

Mirror's Edge™
Shared: Exploration · 3D Platformer · Action-Adventure

Hob
Shared: Exploration · Puzzle · Puzzle Platformer

Webbed
Shared: Exploration · Puzzle Platformer · Platformer

Promenade
Shared: Exploration · Collectathon · Platformer

Praey for the Gods
Shared: 3D Platformer · Exploration · Puzzle Platformer

SpongeBob SquarePants: Titans of the Tide
Shared: 3D Platformer · Puzzle Platformer · Collectathon

Kao the Kangaroo: Round 2 (2003 re-release)
Shared: 3D Platformer · Platformer · Adventure