Games like ReallyGoodBattle
Games like ReallyGoodBattle include Rivals of Aether, Stick Fight: The Game, Rivals of Aether II, Lethal League Blaze, and SpeedRunners. We matched them by the tags players give ReallyGoodBattle on Steam (Action, Indie, 4 Player Local, Local Multiplayer, and 2D Fighter): closest matches first, and among equally close ones the better-known games.

Rivals of Aether
Shared: Indie · 2D Fighter · Local Multiplayer

Stick Fight: The Game
Shared: Action · Local Multiplayer · 4 Player Local

Rivals of Aether II
Shared: Indie · Action · 2D Fighter

Lethal League Blaze
Shared: Action · Indie · 2D Fighter

SpeedRunners
Shared: Indie · Local Multiplayer · Action

A Few Quick Matches
Shared: Indie · 2D Fighter · Action

TowerFall Ascension
Shared: Indie · Action · Local Multiplayer

Duck Game
Shared: Action · Local Multiplayer · 4 Player Local

Move or Die
Shared: Action · Local Multiplayer · 4 Player Local

Lethal League
Shared: Indie · Local Multiplayer · Action

DRAGON BALL FighterZ
Shared: Action · 2D Fighter · Local Multiplayer

ROUNDS
Shared: Local Multiplayer · Action · 2D Fighter

Bopl Battle
Shared: Action · 4 Player Local · 2D Fighter

Mortal Kombat 11
Shared: Action · 2D Fighter · Local Multiplayer

Skullgirls 2nd Encore
Shared: Indie · 2D Fighter · Competitive

Fraymakers
Shared: Indie · Action · 2D Fighter

Mortal Kombat X
Shared: Action · Local Multiplayer · 2D Fighter

Street Fighter™ 6
Shared: 2D Fighter · Action · Competitive

Brawlhalla
Shared: 2D Fighter · Local Multiplayer · Action

Slap City
Shared: Action · Indie · 2D Fighter

Ultra Street Fighter® IV
Shared: Action · Local Multiplayer · 2D Fighter

TEKKEN 7
Shared: Action · Local Multiplayer · Competitive

Timberman VS
Shared: Action · Indie · Local Multiplayer

Nidhogg
Shared: Local Multiplayer · Indie · 2D Fighter