I think that even though Joshua is physically strong, he would fold in fights against punchers, especially against Joe Louis...
Are we taking Joe Louis into consideration, or are we replacing him with AJ? If we do, AJ loses to Louis, but I would favor him against everyone, besides maybe Jersey Joe and would give 50/50 chances of Max Bear and Max Schmeling beating him.
Assuming we’re taking him EXACTLY as he is with a full amateur background, modern day strength and conditioning training, supplements and nutrition and fighting just often enough but not too much then he does quite well. Would that be the reality if he had been born in 1920 ? No.
He'd likely clean out the division up to Louis. At that point, he would have problems with the fast hands and compact combos. He would have to finish Louis before Joe's offense got going. And no one ever finished Louis that early, not even when he was a one-handed fighter.
I fancy that Joshua gets a bit under rated these days, based on his losses, which were what they were. When he unified the belts he was mean and hungry, and it was becoming a genuine problem that nobody was taking him the distance. Anyway, the answer is that he would do very well until he met Louis.
I'm assuming that's what the OP is looking for. The Louis-era guys with their nutrition/training regimens of the day, vs. AJ and his. I'd heavily favor AJ over any of Louis' victims in that case. Schmeling, who I assume most would view as one of the better ones, nearly had his head removed from his neck vs. Baer. How does Baer compare to AJ in terms of skill and power? I'd say not as skilled, and I doubt he hit as hard as the much bigger AJ. Baer himself had practically zero defense, which would obviously be a problem vs. AJ, but perhaps has a (slim) puncher's chance. Who else is likely come close really? The era Louis fought in pretty much amounts to the minor leagues in a H2H sense. The Louis zealots on here will say things like, "JOE SHOWED GREAT RECUPERATIVE POWERS AGAINST GALENTO!", to make a point about what might happen if Joe happened to get tagged by guys like Ruddock, Wilder, or AJ. I mean, seriously? >>>>>>>>>AGAINST GALENTO<<<<<<<<. Is nobody else seeing AJ as a massive leap in opposition for Joe here?? I really don't know what Louis-AJ looks like, but I have doubts Joe just breezes through this.
Only Louis would have a chance, and no, it would not be guaranteed or a walkover. A guy stopped by Schmeling and put down my Galento and Braddock is not walking over AJ.
Joshua gets so underrated in here man, is literally the perfect boxer no, but damn he has more good than bad at the very least, liks the 30s are one the worst eras for Heavy ever, not even going into the fact hes a better boxer than like 95% of that era his physical dimensions alone would make him a boogeyman.
There was some big Heavyweights that Louis had to conquer. Buddy Baer Abe Simon Primo Carnera They were all 6'4+, 240+ pounds, with high KO ratios.