The likliehood of the bout ending with a DQ would be high & Smith had more of those, so solely on that basis I'd go with Zivic.
Skill wise do you think the peak Zivic could beat a peak Smith if they, somehow, didn't foul each other out?
I've no idea mate. I've never seen footage of Smith and they were different sports in their respective eras, so I suspect in a time machine fantasy fight, which fighter was being transported to the others time, would be up against it. Zivic was capable of beating some great fighters and yet lost to plenty of not so great ones.
