It's not even skirts, they literally half-assed by playing it ultra safe to make sure you see it's shorts.
The clothing options are so weird for male characters too. They're either super high cut to the waist, or feminine looking.

>>723137838
They say it's a "Skort" but instead of it being shorts under a skirt, they interpreted it as "half skirt, half shorts"

>>723124442
Basically it's the one that's half shorts on the back and half skirt on the front.