I suppose we'll see what the individual directors say on the matter, as it's really up to them. Personally, I don't think it falls under the Sci-fi/Fantasy/Anime Masq because it's none of those things.
The characters are Pharaoh Tutankhamun a historical figure and Lord Meren who is fictional from the Lord Meren mystery series by Lynda Robinson. The Tut costume was constructed using images from reliefs of him, historical information on clothing and it's construction and other things found in the tomb including recreations of a pairearrings, a broadcollar, the crook and flail and the Diadem. Meren had to be totally taken from description in the books though the author did her research so while the character is fictional his clothing is totally taken from similar sources as Tut though I did design aspects of the costume. It's not really a simple drag in a picture and give it to the judges issue. Not that documentation is an issue as our documentation is extensive.
I suppose the real crux of the matter is would it be considered historical interpratation or historical recreation if it fell in the Histrical catagory because you have a real person and a fictional character