I think AJ would win more rounds than he loses. Bigger reach and imposing power would prevent Usyk from letting his hands go as much. Joshua by TKO mid rounds.
As good as usyk is Joshua is just too big to be troubled by him. I think Joshua gets respect early, usyk goes into survival mode, and then gets stopped late.
Usyk will look good, be mobile and make AJ look silly at times, but will ultimately get knocked out or the ref will call it. I like Chisora, he's a warrior who leaves nothing in the locker room, but come on to be taken seriously as a bona fide HW he should be taking care of of DC inside 10 rounds. He hardly looked good against Witherspoon before that either. In fairness to Usyk he is a buffoon and brings great buffoonery to boxing, but he's got no chance against AJ or Fury, they would eat him for breakfast. Joyce and Usyk on the other hand would be a good match up though for the WBO strap should it be discarded by AJ.