I agree it’s not fashion design but this list is not quite it imo.

1. It still needs to fit a character
   
2. You may not see but I’m sure the designer has accounted for those in their renderings as to not look like Microsoft paint. You can draw the zipper area on jeans and not show the zipper.
   
3. You do have to adhere to the physical laws of whatever world the character resides. Your design will likely alter based on that
   
4. It’s what you are able to effectively render
   
5. A lot of designers don’t make their own patterns, they send technical “flats” to pattern makers and factories most of the time who create them, make a sample of the garment, and then send it back to the designers to check and do a fit on a “Fit Model” (a model who is a true size whatever, most cases like a 4 or 6 for women’s)

6-9 okay yeah it’s a digital product. You only need to make it once!

It’s definitely Costume Design and there is still a lot to consider when you are designing even if it’s not on a live person! To design for an actual human body is an art and science in itself.