Size/speed/athleticism combo is the tough part.
Women can't be bigger, faster AND stronger.....usually only 1 out of 3 and MAYBE 2 out of 3 for genetic freaks.
The athleticism doesn't scale up for ladies so once they hit a big enough size, the gap is too much to overcome. Same reason why you don't see Mexican fighters that are big/heavyweight but also in-shape and not sloppy. They can't scale up in size and maintain the way black fighters can.
You won't see one built like young Foreman, Iron Mike or AJ. If they are, they'll be slow as molasses trying to carry that size. Fast twitch don't lie.