Most Power Cosmic vs Most Powerful Magic

No Mxy. In a straight up scrap no prep no outside help just the two facing off. You pick the two I am not sure for me like Siseg Neg vs Living Tribunal

In Marvel, Power Cosmic shit all over Magic.

Living Tribunal don't have any worthy opponent.

Imo, Sise at his height would have been above LT. But that's speculation on my part.