>>546125756
>>546126006
Shaders & proportions (which they are constantly adjusting) but mostly due to power gap between their 2D vs 3D.

I would say that comparing strictly on 3D Character models in the market it's roughly in order from best to worse
WuWa -> ZZZ -> HSR = GFL2 -> PGR -> Genshin

while 2D character art it's
ZZZ (due to variety) -> WuWa -> GFL2 -> HSR=PGR -> Genshin

Not bothering with Snowbreak, don't count Nikke or other 2D only gachas even if they have live2d.