Games like Running Girl
Games like Running Girl include Haste, Slime Rancher 2, Slime Rancher, Bomb Rush Cyberfunk, and Florence. We matched them by the tags players give Running Girl on Steam (Casual, Action, Indie, Runner, and Colorful): closest matches first, and among equally close ones the better-known games.

Haste
Shared: Action · Runner · Female Protagonist

Slime Rancher 2
Shared: Colorful · Singleplayer · Casual

Slime Rancher
Shared: Colorful · Singleplayer · Casual

Bomb Rush Cyberfunk
Shared: Action · Stylized · Colorful

Florence
Shared: Casual · Indie · Adventure

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

Pumpkin Jack
Shared: Action · Indie · Colorful

Retrowave
Shared: Indie · Casual · Racing

Sparkle 2 Evo
Shared: Casual · Indie · Action

A Hat in Time
Shared: Indie · 3D Platformer · Female Protagonist

Muse Dash
Shared: Casual · Female Protagonist · Colorful

Drift86
Shared: Casual · Indie · Racing

Donut County
Shared: Casual · Indie · Singleplayer

Rise of the Tomb Raider™
Shared: Action · Singleplayer · Adventure

Sayonara Wild Hearts
Shared: Action · Casual · Colorful

ALTF4
Shared: Runner · Action · Casual

Tomb Raider Game of the Year
Shared: Action · Adventure · Female Protagonist

Pikuniku
Shared: Casual · Indie · Action

Passpartout: The Starving Artist
Shared: Casual · Indie · Singleplayer

WEBFISHING
Shared: Casual · Indie · Stylized

Gang Beasts
Shared: Action · Casual · Indie

ATLYSS
Shared: Action · Stylized · Adventure

s&box
Shared: Casual · Action · Indie

Caster
Shared: Action · Indie · Casual