Alternate Shade Man music
Instead of holding the B button as you would in the SNES version of MM7, simply hold the Square button and select his level for his alternate stage music. This will not work if you have beaten Shade Man already.

Versus mode
On the password screen, enter 1415 5585 7823 6251, and instead of holding L+R as you would on the SNES version, simply hold the Square and Circle buttons and press start