Zhang is like a much bigger Foreman. 280 pounds vs 220 pounds. Pro Foreman: Stamina Greater volume Superior at cutting off the ring (although it's hard to see this being a benefit vs Zhang) Pro Zhang: Larger Taller Longer reach Physically stronger Faster hands Southpaw Neutral: Chin- Toss up. Top level chins. Zhang has held up to the power of Hrgovic, Foreman held up to the power of Moorer. Foot speed- Zhang generally plods around, as does Foreman, but both have some speed when they choose to use it. Stylistically I can't help but feel Foreman is made for Zhang, as much as I said Hrgovic was made for Zhang, I feel far more strongly that Foreman is. Generally a boxer used to being the big man fighting a much larger man will lose, and it's hard to imagine Foreman fighting on the backfoot as Hrgovic did at points. It's hard to imagine Foreman hurting the 60 pound heavier Zhang, and despite Foreman's chin, it's hard to imagine Foreman tanking bombs from a 280 pound man punching down. Also, of course, Foreman didn't have the same experience vs southpaws that Zhang has vs orthodox.
The people who beat Foreman didn't stand toe to toe with him Morrison, Young, Holyfield, unless your Muhammad who can take inhuman punishment and do rope a dope. Zhang has no defence and would be an open target for Foreman, there's no fighter in history who could stand toe to toe with Foreman with no defence and survive, Foreman by brutal KO inside of 6 rounds. Although Zhang might have a few surprising moments early on with his power.
It was old Foreman's chin who stood up to Moorer and Morrison's power; young Foreman was 30-40 lbs lighter and physically immature by comparison. Like the young Ali, the young Foreman had inferior punch resistance to the old fat version. This could be seen clearly in the Lyle fight: 6'3, 220 lbs Lyle put Foreman over twice in a slugfest, despite not being the biggest puncher against the small heavies of his day. Zhang is a much bigger puncher than Lyle, a far bigger man, a southpaw, with vast amateur experience rather than someone who came to boxing in his mid-20's like Lyle. I suspect that Zhang would KO a young impetuous Foreman, if Foreman was willing to get in the ring with him. It's similar to a hypothetical matchup between Tua and Frazier.