The beginning of their fight is not my concern
They fought equally, blow for blow matching each other, Moubu even broke his mace towards the end
Worst case scenario he's equal to Kanmei, but really he's stronger, the last moments of their clash portrayed that well
Moubu won this clash clear as day, his strength surpassed Kanmei's
Kanmei was sweating bullets pulling his sword knowing he's about to get fucked