I think the fight most likely looks like the actual fight did, with Foreman blasting Cooney away in lopsided fashion. Cooney isn’t going to keep getting up like Frazier, or even Lyle did.
Cooney has a chance to win. Slim chance but to simply judge Cooney from their 1990 fight is wrong. Foreman was in his 18th fight of his comeback his reflexes and timing were much sharper than Cooney who had one fight (a loss to Spinks) in the last 5 years. And who had spent most of that time away from the ring on Alcohol and cocaine. He was in no shape to be able to handle the pressure and big punches of someone like Foreman getting off his couch for that fight. It was a desperate attempt by Cooney to jump into the Tyson sweepstakes. That’s worse than judging the version of Ron Lyle that Cooney crushed and saying Cooney beats Foreman cause look how easy he beat Lyle and Foreman went life and death with Lyle. Having said all that Cooney was never a physically strong heavyweight. Monster puncher yes but strong no. His frame and legs were on the weaker side. Not quite as bad as Wilder but similar in that Wilder can punch but he also can be pushed around. So yes I expect Prime Foreman to pressure Cooney and get him out of there, Cooney never learned how to survive when hurt and George would hurt him at some point. But as I said he has slim punchers chance - Lyle hurt George and Rusty Cooney actually stunned George pretty good in the opening round of their actual fight. A prime Cooney is much more dangerous. Anyway I see a pretty fun fight with the more durable George getting Cooney out of there somewhere around the 4-5th round.
Indeed a true possibility, but watching Gerry Cooney before he challenged Larry Holmes, it did appear that George Foreman was all offense, who had way better balance than Gerry, who as you pointed out could start fast as well. But if I was a betting man, I would go with Foreman. He was on a mission to emulate his boyhood idol Charles Sonny Liston with his nasty scowl, tough looking walk. Cooney was as the name given to him by the media, Gentleman Gerry Cooney, George was no Gentleman back in 1973. George never gave his opponents a chance to set up, he went out to seek and destroy. Foreman would be younger than any of Cooney's past their prime opponents like Jimmy Young and Ken Norton. And too Foreman had his share of opponents that had seen better days on his way up.
Remember when George Foreman fought Ron Lyle on Jan 24 1976, he was already snake bitten by Muhammad Ali in Zaire. George's ego was deflated, he also had changed styles aquired a different trainer, Gil Clancy. No longer were D. Sadler and Archie Moore with George. A boxer type style was being taught to Foreman by Clancy, that would also lead to his eventual defeat to powder punching Jimmy Young on March 17 1977.
I don't think Cooney bats Foreman under any circumstance aside from the chance he lands flush and he lands first. That said, Foreman is just too much for Cooney. Levels and all of that. And I say that with the utmost respect for Cooney who I really like a lot.
We almost saw this fight. A slightly faded version of Foreman versus a very faded version of Cooney in 1990 and Foreman took Cooney out in two rounds. The Holmes version of Cooney might make it to the sixth before the Frazier I version of Foreman takes him out in a Gatti-Ward version of the heavyweights.
Look at the way George Foreman sent Joe Frazier skating around the ring on Jan 22 1973. Joe had one of the best left hooks in the business, Foreman got tagged with it, withstood it and came back with a sledgehammer right hand to make Joe's night miserable.
To me, the best Gerry looked was when he used his pumping jab to dwarf the Foreman sized Dino Denis, before ending matters by finally hooking off that jab. That's what Cooney would've needed to do. Pump away with that jab in mid ring to keep George at distance. It wouldn't be enough for too long, but I think he keeps Foreman at bay for a little longer. Gerry could jab from far enough away to keep George from using his physical strength. When Foreman does come closer, Cooney's tall enough that he could actually come over the top with his hook. Gerry's lack of punch resistance is the deciding factor, but he could win rounds before it's over. In their actual bout, Gil Clancy tried to turn Cooney cutie, but Gerry looked stilted. Still, he did move George at the end of their opening round with that hook. Unfortunately, it woke Foreman up. Cooney should've done what he did with Denis. Pump that jab in George's face constantly, then hook off it as a surprise. Again, look at Cooney-Denis and Foreman-Denis. George is the same height and reach as John. Gerry was tall enough with a long enough reach to score jabs without being jabbed in return. Cooney never defeats Foreman. But he could have more success than is usually supposed, prime for prime. Victor Valle should've cultivated the Denis template.