I believe zoro entered onigashima and most likely wano stronger then king
that being said zoro usually enters most of his fights stronger then his opponents but with some caveat. He was outclassing mr. 1 in their fight he just couldn’t cut him, zoro decided not to use ashura out the gate against kaku at ennies lobby because plot, down a sword against ryuma, was superior to pica but pica Kept running
i believe zoro will enter a fight against king wounded but will learn to use acoc in base or learn to extend ashura. So I guess I’m saying just because zoro was already stronger doesn’t mean he can’t benefit.