Oda is once again having Zoro waste time fighting on opponent who's not at his level and he can easily quickly defeat. The same thing happened against Pica, Monet and Hyouzou. Oda has to find someone for Zoro to fight to occupy his time until he's ready to move on with the plot.
The colorspread once again proved Zoro was not using KoH or ACoC.
Zoro ACoC is drawn as black lightning that wrap or flow around his swords. Not a tiny discharge that requires a close-up of the sword to see. Claiming Zoro is using ACoC or KoH is no different than claiming Luffy and Lucci clashed was a ACoC clash because there was black lightning.