Can Taliyah please have a Toph inspired skin

Bad idea, they can't do a toph skin it'd be like straight up stealing, and before you say "but she's an earthbender" if you look at her style and her ability's her Q looks like razor sharp needles, the rocks look tipped at the end like weaving needles, The E looks like a weave of rocks, and her ult looks like the under and over thing in weaving, she's more than unique on her own, just because she throws rocks doesnt mean she needs a skin inspired by toph, She ran away from home because she can't control her powers, and toph was quite boastful/confident in her abilitys they are like opposites

She does, it's called Classic Taliyah

Well, Sivir does have a Xena skin, even though half the population of the game probably won't know who Xena is anymore (it's sobering to know that a vast majority of people today won't know that show).

I don't think Avatar has been out long enough to be in the public domain yet so that's tricky. It's also not based on historical figures such as Lu Bu for Xin Zhao. I'd need to do more research, but from a legal standpoint, at first glance it seems impossible.