While the clothes are obviously a fusion, the girl wearing them has Yukari's hair and Yukari's eyes (also, Yukari's expression, even if this is much more subjective).
While the clothes are obviously a fusion, the girl wearing them has Yukari's hair and Yukari's eyes (also, Yukari's expression, even if this is much more subjective).
So I think it's Yukari cosplaying.
If you look closely the hair is gradient, it is both Yuyuko's pink at the back and Yukari's yellow at the front.
