Context: the art is based on concept art that showed Chel wearing this outfit of a poncho and literally nothing else. (If someone's wearing an outfit from the concept art phase, does it count as an official alternate costume or just a regular alternate costume?)

Sproq981 said:

(If someone's wearing an outfit from the concept art phase, does it count as an official alternate costume or just a regular alternate costume?)

I think it's prototype design.