Fiora is not supposed to look sexy
Look. I know we are all sad about Fiora's old splash being replaced. I remember how it was the first splash art that caught my eye when I first entered the store purchase champion section. Fiora was the first champion I really save up ip for.
However. As much as the old splash art is elegant and badass the new one does succeed in one area: Delivering Fiora's character
Fiora according to her lore is not a "bad ass femme fatalae" sure she is a female who is super skilled at fencing but she is not the hero lady fantasy who saves the day. She is a snob. And for runeterra's sake let her be that. A female champion mustn't satisfy your awe, let Fiora resemble her personality.
It is clearly stated in her lore and in her voice over that she is confident, ruthless, stuck up and vain. Her old splash art makes her look more like a wild mercenary while her new really brings out that posh yet cold noble woman.
If there is something you should complain about on the new splash art, it should be her broken back, just wtf is that about.