You can also try deleting your save data for SSBB, right click SSBB in the game list and choose "Open Wii Save Folder". Delete all content of the folder that will open and the game should create a new save file when you boot it again. You could also try disabling "Enable cheats" option...
Avell A70 MOB: Core i7-11800H, GeForce RTX 3060, 16 GB DDR4-3200, Windows 11 (Insider Preview)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)