Kotonoha could see her, but couldn't react. FTE to Naruto.

Faster that Naruto's trained eyes could follow, Setsuna closed the distance to Kotonoha. Next thing he saw, the small half-Kitsune had jumped until her waist was at the swordswoman's face level. It was a wide, midair roundhouse kick aimed at Kotonoha's face.
Setsuna's whole body glowed with a coat of lightning.
Kotonoha was able to see the attack. Her body could not keep up with it, though.