Usyk that fought Briedis, would lose to Beterbiev that fought Smith. Beterbiev is older than Usyk, let's not forget that.
Bellew would probably be comfortable for the early rounds, finding his range and moving well. But every round that goes by Beterbiev’s power shots will slowly take their toll, weakening Bellew until he finally breaks down under the pressure of those punches, and AB finishes him off by Round 7
He beat him in the amateurs, but that was a green 20 year old Usyk. A prime 30 year old Usyk would be the heavy favorite and for good reason. But it's a fantasy match up I'd love to see anyways.
Those 10 years of experience go a long way for a boxer with Usyks already high ring IQ, but like you say it is a fantasy fight.
I'm well aware of that.... back in 2007 when Usyk was 20, when they were both at Middleweight, a year removed from his loss to Shawn Porter. He had two more attempts in the amateurs at a higher weight, and couldn't do it. I hate to break it to you, but they're two weight divisions apart now, three if you count Bridgerweight, and yes... AJ hits harder than Beterbiev. Usyk would brutally KO Beterbiev.