Games like Marble Odyssey
Games like Marble Odyssey include Portal, Kao the Kangaroo: Round 2 (2003 re-release), ATLYSS, WEBFISHING, and A Hat in Time. We matched them by the tags players give Marble Odyssey on Steam (Action, 3D Platformer, Casual, Puzzle Platformer, and Collectathon): closest matches first, and among equally close ones the better-known games.

Portal
Shared: 3D Platformer · Puzzle Platformer · Action

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

ATLYSS
Shared: Action · 3D Platformer · Character Customization

WEBFISHING
Shared: Casual · Character Customization · Cute

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

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

Pumpkin Jack
Shared: Action · 3D Platformer · Collectathon

s&box
Shared: Action · Casual · 3D Platformer

SpongeBob SquarePants: Battle for Bikini Bottom - Rehydrated
Shared: 3D Platformer · Action · Casual

Human Fall Flat
Shared: Puzzle Platformer · Action · Puzzle

Placid Plastic Duck Simulator
Shared: Casual · Collectathon · 3D

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

Spyro™ Reignited Trilogy
Shared: 3D Platformer · Action · Collectathon

Tower Unite
Shared: Casual · Character Customization · Action

Pikuniku
Shared: Casual · Action · Indie

EDGE
Shared: Action · Puzzle Platformer · Casual

Lil Gator Game
Shared: Casual · 3D Platformer · Cute

Yooka-Replaylee
Shared: 3D Platformer · Collectathon · Character Customization

Planet of Lana
Shared: Action · Puzzle Platformer · Casual

Disney Speedstorm
Shared: Action · Racing · Casual

PICO PARK
Shared: Puzzle Platformer · Casual · Action

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

Monument Valley 2
Shared: Casual · Action · Puzzle Platformer

KeyWe
Shared: Puzzle Platformer · Casual · 3D Platformer