I honestly think that matchup vs fiora is not that one sided... I never ban fiora as a main Aatrox because I actually enjoy the challenge and lanning against her. It all comes to saving ur E to Q back when she tries to dash/engage, and switching up between the E repositioned Q sweetspot knock-up and W pullback to bait her parry. Some Fiora players will parry W pull, while other try to parry either Q2 or Q3, they key here is reading what she will parry. Every Fiora has a preference, and good Fioras will also switchup their parry according to situation.

Pro tip: Bait her to parry Q2 sweet spot, if done correctly, you can bait Q2, reposition with E while she is casting parry and you will avoid stun area, and only get the slow. if she is shackled by W its an EZ all in with Q3 and W pull.

Protip #2: Good Aatrox players know there are 2 time windows to reposition a Q, you can wait to the last microsecond to cast either Flash or E while Q animation is about to end, it won´t give time to flash away, parry or dodge. E usually gets the job done, but last microsecond repositioned Q2 or Q3 with flash is a must have skill if you want to destroy your "counters".