Fiora's % True damage would "maybe" be tolerable if her Riposte...
Didn't make her immune to ALL types of damage AND crowd control effects. Who even thought to put that on her while she deals a considerable amount of damage and has a heal too? The only champions who have a damage block is Jax and Master Yi, but it's not to an extent that they aren't vulnerable to anything. Jax can still be hit by spells and Master Yi is vulnerable to mitigated damage and crowd control. If she parried all BASIC attacks and has a slight reduction to spells (meaning you can still land crucial damage on an assassin), then things would be fine.
However, that's not the only thing that is frustrating... If her Riposte hits you, you have reduced movement and ATTACK speed. Did she really need to have an attack speed slow? Even Darius lost his attack speed reduction after his rework. Not only that but if she absorbs hard CC, she gets a stun, which in my opinion is just too powerful in most cases since she already does % true damage and has a heal post-6.
Riot or Meddler... Or any Rioter lurking around... Did she really need that much power pasted into this one ability?