Jeez, can't you chill out and just have a little fun for once? Especially considering that this is the cover for some ELSE'S fan fiction. I'm well aware of how you feel about alternative interpretation of the characters, but not every has to-or should be-exactly as depicted in cannon 100% of the time. In fact, it only really has to be canon in the official works. Other than that, artists are free to draw what they want, writers are free to enjoy what they like, and whoever wants to is free to enjoy it. You don't have to look at it if you don't want to.
Fanfiction. Fan fiction. By definition it runs on alternate interpretations, so artists are free to do pretty much anything as long as the core of the character stays intact. Now, given that in Touhou only the most crucial information is given as canon, that gives artists a very generous leeway, permitting even completely new characters, such as the Bruce Lee-esque miko we see here.