I think it will be minimum 3 full chapter, and there should be proper build-up of student vs teacher theme. The flashback of their training session together but from Mihawk's POV, the past of Mihawk and what motivates him to teach Zoro...and his hopes for Zoro as a representation of WSS' future generation.
The choreo would be both fast and destructive, they may display the highest environmental AoE destruction rate in the manga, imagine they both cut each mountains in their battle route over and over, leaving long trace of mountains being split open.
I have high hopes regarding character interaction, personality development, and point of view as swordsmen, for this fight.