Super SMN5 64 is a fan-made game, likely for the Nintendo 64, that's probably a crossover fighting game. The "SMN5" may refer to specific characters or elements in the game's design. Further details on its content and gameplay would require looking into the fan communities involved in its creation. As it's a non-official title, its features are not standardized.

Super SMN5 64

Super Smash Bros. Sonic 2 Mod