Creators of Super Smash Flash Making an Official Indie Crossover

Fraymakers looks to be the most ambitious indie crossover fighting game yet, with a successful Kickstarter campaign that is still ongoing.
Successfully funded on Kickstarter!

The Nintendo Direct Super Post — Everything You Need to Know — GameTyrant

Indie Tournament! (An Indie Smash Bros Game) Fan Casting for Make your Own Crossover

SSBU Roster but with Indie characters only. : r/SmashBrosUltimate

Super Smash Bros: The Cataclysmic Multiverse by ScytheJackal on DeviantArt

Super Smash Bros. Crusade Now Has Over 60 Characters, 24 Stages, And An Online Mode - Siliconera

The Indie Platform Fighter Taking On Smash Bros - Fraymakers

Fraymakers - Wikipedia

Games like Smash Bros. for PS4, Xbox, PC, and Switch: 8 great brawlers to play next

My Smash Wishlist by SonicPal on DeviantArt

Super Smash Flash 2 Kbh

Super Smash Flash 2 Genesis, Game Ideas Wiki

Fraymakers - an indie crossover platform fighter from the people behind the Super Smash Flash games

Fraymakers (Steam) Early Access Impressions — Forever Classic Games

Super Smash Flash - Wikipedia

Fraymakers - an indie crossover platform fighter from the people behind the Super Smash Flash games