-killerbee cant use tailbeast mode( but can still use his tentacles while not awakened)
-no prep time
takes place on a open grassy terrain
-killerbee has samahada
I'm not too familiar with CURRENT Zorro but from my observations in the past (Pre-time skip), Bee loses in this battle. I don't see Bee defeating Zorro in a sword fight. With the assistance of the 8-tails, perhaps he can put up a tough fight but I'd still go with Zorro even then.
Better give B his beast forms because this is a slaughter house in favor of Zoro. Even with the beast I still see Zoro as the winner just not nearly as easily. He is just way faster and stronger than base B and is more than capable of cutting B even in tailed beast form.
Could not have said it any better myself.