I think Kasumi's costume was a fan made costume, for a contest or something.
And since costumes is an important signature of DOA in my opinion, they should either organise a "Create your costume" contest, or propose the fans polls to determine which costumes from the past should make it.
... no ?
And, I really want everyone's legendary costume to return. Kasumi already has her blue classic, Ayane her C1 from DOA2, Lei Fang her red dress, Hitomi her karate gi, Christie her beige assassin suit, and Kokoro her pink kimono.
Tina should have her black catsuit, Helena her opera dress (C1 or C2 from DOA2), and Lisa her luchadora costume.
I really like Tina's torn grey dress from DOA2. It was... sexy.