Luffy would break Zoro's spine, stop it. The man has fought Doflamingo, Cracker, Enraged Army, Katakuri, Fujitora, Linlin and Kaido. The sheer gains in haki alone puts him ahead of Zoro. At this stage Luffy has pulled substantially ahead of all his peers. One G3 punch had Kaido thinking of characters compared to PK calibers. The best indication of their standing is the initial confrontation with Kaido. One might argue Zoro's not mastered Enma.
Yet, the fact of the matter is Luffy in an inferior mode rattled Kaido. Furthermore, as Zoro is mastering Enma, the potency of Luffy's existing ryou will be growing as well. With that said, goddamn Zoro is an absolute fukking monster. Enma might be the single greatest swordsman's powerup. Its drains CoA and magnifies it in perpetuity. Madness!! Basically even Roger would hit harder if he wielded it. Shishi Sonson is about to hit different from this point onwards.
There's also the fact Linlin is cognizant enough to acknowledge its lethality. On account of his hax - durability negation, radio-knife, gamma-knife, shambles -- I thought Law would be the pest. If Zoro were to master Enma and unleash Asura in this battles, he's about to become a serious problem. He's as ruthless as Kid, as lethal as Law, as composed as Killer and potentially as destructive as Luffy. His mindset as of now is set on killing Kaido. Honestly, the only weakness in his game is range. I'd fukking lose it if says fukk Law and pulls an Oden -- jumping straight for Kaido.