Probably closer to 500 considering models for juveniles and both sexes. Which is why I think PZ2 will take a page out of JWE2 and just not bother for the vast majority of species. They're already using HD textures on models with loads of triangles, no point in re-inventing the wheel even if some of them have cartoonish proportions.
Frankly the only models with which I had serious issues are the Malayan tapirs (these were objectively the only reskinned animals in the whole game, they even kept the mole from the Baird's tapir) and the infamous bintu-wrong prior to the SEAAP's release. Because I'm fine with every other model, I'd prefer keeping everything from PZ1 in PZ2's base game.
And I'd prefer seeing PZ2 get delayed for as long as possible, ideally so they can figure out how to make the core gameplay loop fun and rewarding.
I do think they are going to remake some animals to current standards and update the fur textures in most of them.
But i believe they are aware of the critiscism for animals like the lion, bears, wolves, iguanas, snakea, okapi, orangutan. I expect them to adress all those at the very least and i hope the spotted hyena, all the cats in base game and wild dogs get the same treatment. I think those are pretty much the animals that need complete reworks because in their current form are pretty much unplayable because of how bad they look compared to DLC animals, specially the ones that have some kind of "variant" in DLC to compare them with.
Then you have other animals like the bison, giraffe, zebra, etc. That need a glow up and an up to date rework but are not as bad as the other ones i first mentioned, so they are second priority. But i do expect things like bringing the zebra model to the ass rig at the very least and so on.