Fiora Counter Tips
When her Q(Lunge) is on cooldown, that's a perfict time for you to punish her since it is the only mobility spell she has.
In late game teamfights never stay too close one to another because if Fiora buys Tiamat/Ravenous Hydra thats a massive AEO damage she deals.
If you picked a tanky top champion, buying Thormail will be a reason to worry for Fiora.
Try to bait her and waste her Burst of Speed before you duel her and go hard onto Fiora.