They completely changed her design in the game to be younger and less boing-boing?
They did indeed change her design, they did however not purge it from the game and some bits and pieces such as the shirli pfp still use her old look's head. Including the crossed hairclips, different eyecolor, and generaly vastly different look that (how i would guess it) western audiences dont like that much?
It would explain why nemesis is more boin-boin though, not that nemesis is actually boin-boin as she is one of the few boobed characters that do not have jiggle physics enabled. (Which given how jarring it looks with smaller breasted characters and more loosely fitted outfits, makes sense-ish?)
Either way, you could almost say this shirli is not the shirli we know of, maybe one from a different timeline if i were to speculate.