Choose five Wlad-victims to beat prime Joshua

"Ibragimov that fought Wlad was literally on the verge of retirement - disappointment of a performance"

Right. Sultan's heart wasn't in it at all; he wanted the juicy payday and to get out of the game as fast as possible. He even said something like "I realised halfway through the Klitschko fight that I'd lost". It was to a considerable degree a survival mode performance.

Austin claimed that Ibragimov hit him harder than anyone else he faced but that's typical fighter BS to big up the guy he dropped and drew with; the fighter who hit Austin hardest was the guy who sparked him in 2 with a flurry of left hooks. Sultan's fights with Mora, Whitaker, Lawrence, Cole and the Austin KD suggested that he had decent power but he certainly wasn't a Corrie Sanders puncher. That being said, neither was Andy Ruiz and Ibragimov was certainly a bigger puncher than Byrd, as well as slightly more competitive on paper with a better version of Wlad than 2000 Byrd was. So Sultan's not a bad pick. And he'd likely find more opportunities to land on Joshua than Wlad, so he may not become disheartened halfway through in that matchup.

"Wlad feasted on small guys and got knocked out by small guys."

The same could be said for Joshua. He beat 41 Wlad in a life and death, aside from that his best SHW opponents have been Breazeale and Helenius, both of whom took him 7. Wlad's best SHW opponents beaten were Thompson x2, McCline, Wach, Austin and Jefferson and he had vast experience sparring Vitali.

Wlad sparred Joshua for the Pulev fight and by all accounts got the better of him. He would have taken more from the spar as he's smarter than Joshua, Joshua's patterns would be very fresh in Wlad's mind and Joshua's confidence would have been affected, so it's a very lopsided hypothetical. There was also very little clinching in Wlad's fight with Joshua, Joshua may have even clinched more than Wlad did in that fight.

 

Wlad loved the clinch against small opponents because it was pretty much totally safe, drained the opponent's stamina, frustrated them and ran the clock down. I don't think he needed to clinch anything like 120+ times to beat Peter in the rematch for instance, I think it was extreme risk aversion (if he could get away with it, which he usually could) and a desire to maximise longevity. Helenius got a lot of praise for KO'ing Peter straight after Wlad but iirc Wlad absorbed something like a quarter or a third as many punches as Helenius using his octopus tactics and about half as many as Vitali did in his Peter fight.

 

2004 Brewster isn't eligible as one of the five picks out of ten because he's a Wlad-conqueror rather than a Wlad-victim. My choices would be Williamson, 2005 Peter, 2008 Thompson, Haye, Povetkin. The only fighters on the list that I don't seriously consider are Chagaev and Pulev.

"Prime Povetkin" per se isn't an option. The hypothetical assumption is that you can choose the same versions who fought Wlad. We both believe that the Povetkin who fought Wlad didn't have the power he developed later, I've read Briedis alluding to this and even Wlad himself:

“That is going to be an extremely entertaining fight. I definitely think Povetkin has ability to win this fight, but also Deontay can do it. And he (Povetkin) definitely has improved in the years since he lost against me. He definitely got better. I even think that my fight with Povetkin these days probably would’ve looked a bit different. I definitely think it’s something that’s exciting because you don’t have a favourite in this fight, I would say 50-50, it can go either way.”

But that's not to say he's not a solid pick. 34 year old Povetkin would be quicker, more durable, fitter and more confident than the high mileage career pressure fighter 39 year old Povetkin, still with more punching power than Ruiz. I'd favour some version of Joshua over all of Wlad's victims but Povetkin would be one of the most likely banana skins in my opinion.