Fiora can Teleport before 0:15 by using her Q.

Bug: Fiora can use her Q before 0:15 (when the barrier falls down) and have the ability to Teleport. Champions are not able to Teleport before 0:15 and the turrets are not targetable until several seconds into the game. Fiora can Teleport before 0:11 and end the spell before 0:15, which leaves herself in Nexus and the spell on cooldown. She can use in between 0:11 and 0:15 and be able to Teleport to the location.

It's a small bug but seems to be unintentional.