and for the sake of this battle,smith has cross' powers and abilities
What's the point in that? It means it's no longer Cross v Smith. It effectively proves that Cross would destroy Smith easily so to counter it you basically have to make Smith into Cross which makes the whole thing pointless.
It's not exactly difficult to find people with comparable skill sets to fight each other without gimping one or making one more powerful than they actually are. Just put a bit of thought into it.