Since it's Composite Godzilla (Feats from all comic sources like Godzilla in Hell), Godzilla actually wins due to feats, powers, speed and his Super Godzilla form, which, from what I know about it, is really powerful. Composite Zilla is like REALLY fast. He traveled 500 million light years in one single leap. He also has an insane healing factor, he regenerated from a single cell, also, he's only weak to man made electricity, and his "second" brain.
So yeah, G-Zilla wins.
Ultra instinct is low 4D. Devin Godzilla is easily beyond dimensions.
And Godzilla out haxses him to fuck.