I'd favour Joyce here, but it depends on if he can take Wilder's right hand. If he can, or can neutralise it like he did Dubois's, then he pounds Wilder into dust.
I have previously said Wilder but having seen him against Zhang who simply plodding forward and had no problem cutting off the ring and getting at Wilder, I think the even more aggressive Joyce does a number on him. We all know Wilder has no inside skills and can't fight on the back foot, he needs that space to land and if he doesn't land flush early or has such huge advantages him height and reach to stay away, he will get back up. The Breazeale and Helenius fights are misleading while they both pressed forward they are both guys who fight at range so while they backed Wilder up they also stay at Wilder's most dangerous range, Zhang didn't do that he didn't just push him back he got inside and at that range Wilder is useless. Joyce doesn't do this either he can fight at mid range and close range and work the body and head with hooks like he did against Parker, he doesn't stand off to land straight shots all the time like Helenius and Breazeale, so won't give Wilder that space to set and load the long right hands very often. Joyce breaks him down stops him inside 5 rounds.