I might pick Rocky under those conditions. Evander was still green at that stage and he hasn’t yet developed the physical strength to take the kinds of hammerings that he’d later endure over 200 lbs. The first Dwight Qawi fight saw him hospitalized
Holyfield too tall, long, fast and skilled... Too good on his feet, too. This is really one where Rocky is taking 4 to land 1. I don't think that equation plays out over 8-10 rounds before he is on the bad side of the sum.
I think that Holyfield from Qawi 1 or earlier would be unequivocally stopped by Rocky. From Qawi 2 to De Leon, a much closer fight by Marciano UD
Dear The Seamus, That's when he got bigger. Had he been 190 pounds, he may have been stopped by Tyson and Lewis.