Not 100% sure what's going on here. It's definitely Vivio's outfit but the hair is somewhat different and there's no heterochromia. The artist did draw Vivio in this update, in another image. Tagging it as an original character cosplaying Vivio until someone can point out otherwise.
No, I'm pretty sure that's Ixpella from the SSX sound stage. She's a genetically-engineered Belkan bioweapon like Vivio who acts as a control system for a kind of corpse soldier called the Mariage.
