Actually, there are a bunch of flaws with this design, as pointed out here.

TL;DR:
>The shin and arm guards are too narrow to be useful, plus if she has those arm guards, she would’ve failed her exam against Eraserhead because she wouldn’t have been able to create that metal loop around her arm that let her escape his binding.

>The zipper doesn’t work because in the event she needs to rip open her outfit to create something, she’s got to fumble with a zipper instead of just opening her chest window. It’s going to decrease her reaction time and make it harder to create larger items.

>The bits connecting her bottom with her top are going to shred when she creates something large.

>The glove would be a problem if she needed to create something in her hands, either discreetly or because she’s bound up, because it’s going to be stuck inside her gloves.

>The artist just wanted to cover up Momo's cleavage and didn't think the design through.

That's costume actually looks more useful than original.