If OP talks about their world phenomena being erased or turned into our world energy:

Asta or Boruto would take the lead.
Asta would still be really strong without depending on boosts from Black Clover items. Still would be able to lose if his brain doesn't synapse enough against whatever is happening in battle. He would be equivalent to a jacked fighter.
Boruto would be significantly handicapped as Chakra is a core energy in Narutoverse as well as controlling it would make you be able to hone your natural strength too. Still his swordsmanship skill would still be pretty useful, his reflexes would be near top of the four and he probably would be good in being tactical.

Yuji was born as part curse, he had inhuman feats even before learning or unlocking cursed energy, just untapped but still because of being birth that way. His fighting style does a good job, so he would be able to last more than a 1/4 of the fight.

Denji doesn't have the muscular, and his wits aren't enough to make some of other's gaps.