Games like Anima Flux
Games like Anima Flux include Hollow Knight, Hollow Knight: Silksong, Ori and the Will of the Wisps, Nine Sols, and Dust: An Elysian Tail. We matched them by the tags players give Anima Flux on Steam (Adventure, Action, Indie, Metroidvania, and 2D): closest matches first, and among equally close ones the better-known games.

Hollow Knight
Shared: Metroidvania · Platformer · Indie

Hollow Knight: Silksong
Shared: Metroidvania · Indie · 2D

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

Nine Sols
Shared: Metroidvania · Action · 2D

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

Rain World
Shared: Indie · Exploration · Atmospheric

Skul: The Hero Slayer
Shared: Action · Indie · 2D

Constance
Shared: Metroidvania · Action · 2D

MIO: Memories in Orbit
Shared: Metroidvania · Indie · Platformer

Rogue Legacy 2
Shared: Action · Metroidvania · Indie

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

Axiom Verge
Shared: Indie · Metroidvania · Action

Gato Roboto
Shared: Indie · Action · Metroidvania

SANABI
Shared: Action · Adventure · Indie

Hyper Light Drifter
Shared: Adventure · Indie · Action

Salt and Sanctuary
Shared: Metroidvania · 2D · Action

Dead Cells
Shared: Adventure · Metroidvania · 2D

Unbound: Worlds Apart
Shared: Adventure · Indie · Metroidvania

Cuphead
Shared: Platformer · 2D · Difficult

UnEpic
Shared: Indie · Metroidvania · Action

SteamWorld Dig 2
Shared: Adventure · Indie · Action

ANIMAL WELL
Shared: Metroidvania · Exploration · Platformer

Blasphemous
Shared: Metroidvania · 2D · Indie

Guacamelee! 2
Shared: Metroidvania · Action · Platformer