Yu did say Shenhua might change her clothes through the game... also, in the teaser her hair length varies.
There was also this from last December:
I was pretty convinced this was of the new model (the scarf/snood around her neck is smaller than the E3 2015 model at least, and we know the new models were in production at this time), so... I wouldn't say Shenhua's old costume is gone
just yet.
They could just be having trouble with stuff like the sleeves. Notice how Shenhua's new outfit doesn't have the open, loose sleeves of her original costume. My guess is they wanted them to be realistic by having the sleeves as a physics object (like parts of Ryo's jacket), but haven't quite got there yet, or have abandoned it altogether due to difficulty.