Regarding your trivia at the end, I had to do a quick bit of research but yes, both "cheongsam" and "qipao" are the actual names for that chinese dress. "Qipau" is Mandarin and the older term, "Cheongsam" is Cantonese, so both are correct. As for which to use, it doesn't seem to matter too much, "Cheongsam" apparently tends to get used more to describe the more form fitting version we see here, while "Qipau" tends to get used to refer to them in general, but most notably for the traditional style that isn't as form fitting and doesn't show off your legs. I'd say if you wanted to change it, you should use "Cheongsam", but I don't think it matters too much.
Also there's nothing stopping her from wearing leggings so she's just making this worse on herself lol.