So I'm writing this up just because I can, lol also in case I'm not the last person to actually figure this out, and for future player benefit.
While I was bored today, I decided to mess around with the dragon ball mechanic to see how to pick what wish. As it turns out, not complex. 4 wishes, 4 directions on the pad.
Up: active character heal.
Right: Ultimate power, aka second sparking blast.
Down: Blue health heal for entire team.
The selection does not change if you press multiple times, so feel free to just mash the button once the animation starts, press X as soon as you hear the selection sound of whichever wish you want.
Probably not a thing that gets used often in real matches, but hey, now it's here.
"I used to be an adventurer like you, then I took an arrow in the knee."