Dustin Nichols, Buster Mathis sr, Two Ton Tony Galento, Harry Funmaker, Butterbean and King Hippo would make a perfectly rounded camp stable.
Deontay Wilder could help him to improve his punch resistance but they would have to medicate him with sedatives in order to save Joshua’s life, so not really a good idea.
Fury could show him how to get up from a knock down when you have been partially embedded into the canvas and Wilder could teach him how to throw punches with absolutly no technique(windmill technique) and the proper dance or wobble effect when hit.
I couldn't have typed better myself but is Nichols and Butterbean available in between cleaning out All You Can Eat Super Buffets to spar with Joshua for his devastating second Defeat at the hands of the Snickers Bar King??
Arreola (guy with loose muscles, but muscle memory) Mansour, (height and activity) Joey Dawejko, Tank Williams, (dimensions)