Games like GunGirl 2
Games like GunGirl 2 include Hollow Knight: Silksong, Hollow Knight, Dust: An Elysian Tail, Bloodstained: Ritual of the Night, and ICEY. We matched them by the tags players give GunGirl 2 on Steam (Action, Indie, Adventure, Metroidvania, and Zombies): closest matches first, and among equally close ones the better-known games.

Hollow Knight: Silksong
Shared: Indie · Metroidvania · Platformer

Hollow Knight
Shared: Metroidvania · Indie · Platformer

Dust: An Elysian Tail
Shared: Action · Indie · Metroidvania

Bloodstained: Ritual of the Night
Shared: Action · Metroidvania · Adventure

ICEY
Shared: Action · Female Protagonist · Adventure

Iconoclasts
Shared: Indie · Action · Metroidvania

Nine Sols
Shared: Metroidvania · Action · Indie

SteamWorld Dig 2
Shared: Adventure · Indie · Action

The Vagrant
Shared: Action · Female Protagonist · Metroidvania

Ori and the Will of the Wisps
Shared: Metroidvania · Action · Adventure

Rogue Legacy 2
Shared: Action · Metroidvania · Indie

Skul: The Hero Slayer
Shared: Action · Indie · Metroidvania

Deadlight
Shared: Action · Indie · Zombies

Ghost 1.0
Shared: Indie · Action · Metroidvania

Gato Roboto
Shared: Indie · Action · Metroidvania

Dead Cells
Shared: Adventure · Metroidvania · 2D

Axiom Verge
Shared: Indie · Metroidvania · Action

Constance
Shared: Action · Metroidvania · Indie

Blasphemous
Shared: Metroidvania · Indie · Action

Monster Boy and the Cursed Kingdom
Shared: Action · Adventure · Indie

UnEpic
Shared: Indie · Action · Metroidvania

Guacamelee! Gold Edition
Shared: Action · Metroidvania · Indie

Zombotron
Shared: Action · Adventure · Indie

Shantae and the Pirate's Curse
Shared: Metroidvania · Action · Platformer