Who Would Win?

I'm pretty sure fireball will win. He is a ball of fire

Now he’s just ball.

Basically, he can I denitfy a foe’s weakness just by looking at them. If he can’t find a weakness, he just uses brute force.

Depends. Does Markus have a Soul Form?

Yep.
Top:Hidden wings
Left:Demon form
Right:soul form

Placeing my bets on Markus

Same

yeah.