>>41994386The cat sprite we knew about for a while, but the leak includes a sprite sheet that matches the order on other sprite sheets on confirmed official production material (Famitsu, NHK)
Other than that, everything else included either can't be confirmed or was already known beforehand. I guess if you could have access to an early sprite sheet somehow (for example, having seen it either in a game expo or a magazine we don't know about) the rest could be fake as well, then again, there are lots of missing stuff from the leak (the 9 unused Kanto medal names, the icons used for each monster in the status menu which were present on the book cover, "bird" type) that I know I would've used if I had to manufacture a fake leak.
Obviously the most jarring part of that leak is the omission of front sprites, but I think that has something to do with each monster having multiple front sprites from the very beginning, back from when it was originally 2MB (pic related, this document seems to suggest that the "second type" of sprites, probably the Blue ones, had unique back sprites as well) which might suggest maybe they were handled separately? Back sprites weren't as important but the front sprites had to be manually selected and tweaked for release or something like that?