Games like Brotherhood United
Games like Brotherhood United include Broforce, Shovel Knight: Treasure Trove, Katana ZERO, Skul: The Hero Slayer, and Sonic Mania. We matched them by the tags players give Brotherhood United on Steam (Action, Indie, Pixel Graphics, 2D, and Platformer): closest matches first, and among equally close ones the better-known games.

Broforce
Shared: Action · Pixel Graphics · 2D

Shovel Knight: Treasure Trove
Shared: Pixel Graphics · Platformer · Indie

Katana ZERO
Shared: Action · Pixel Graphics · Platformer

Skul: The Hero Slayer
Shared: Action · Indie · Pixel Graphics

Sonic Mania
Shared: 2D · Platformer · Great Soundtrack

Cuphead
Shared: Platformer · 2D · Indie

Super Meat Boy
Shared: Indie · Platformer · Pixel Graphics

SANABI
Shared: Action · Pixel Graphics · Indie

Duck Game
Shared: Action · Pixel Graphics · 2D

Hotline Miami
Shared: Action · Indie · Pixel Graphics

Celeste
Shared: Pixel Graphics · Indie · Platformer

The Messenger
Shared: Pixel Graphics · Platformer · 2D

Gravity Circuit
Shared: Action · Indie · Pixel Graphics

Pizza Tower
Shared: Indie · Great Soundtrack · Pixel Graphics

Axiom Verge
Shared: Indie · Pixel Graphics · Action

Vampire Survivors
Shared: Pixel Graphics · Indie · 2D

My Friend Pedro
Shared: Action · Indie · Shooter

Hollow Knight
Shared: Platformer · Indie · 2D

The Binding of Isaac: Rebirth
Shared: Indie · Pixel Graphics · Great Soundtrack

Out There Somewhere
Shared: Indie · Pixel Graphics · Platformer

Hotline Miami 2: Wrong Number
Shared: Pixel Graphics · Action · Great Soundtrack

Rivals of Aether
Shared: Pixel Graphics · Indie · Platformer

Risk of Rain (2013)
Shared: Indie · Action · Platformer

Freedom Planet
Shared: Action · Platformer · Indie