Who does Wilder spar? Anyone actually know? Judging by the state of his resume and what's he actually paid his overmatched opponents my guess would be amateurs and club fighters. And Malik Scott. Personal friend and professional sparring partner.
AJ needs tall rangy guys with speed and power. Cruiserweights like Okolie are a good shout. Wilder can basically spar any big stiff idiot. My suggestion would be David Price or maybe his gay lover Tony Bellew.
Both should try and get Yoka in their camps. He’s fundamentally sound like Joshua, and he’s big and athletic. I think he could prove priceless for Wilder. Joshua should still use him for his height and reach, as well as the fact that he’s a quality operator and therefore will naturally improve his game.
Joshua should take a failed college basketball player and posse the vessel with several Egyptian deities
Malik Scott is one of the best sparring partners in the business and would help either guy very much...especially Joshua. However, I doubt we'll see him in either camp.