[BetteT]

I looked up the German word "stellvertretender" on two different places and I got "acting one" and "more on behalf" .... which means, to me, that she is acting for someone else, so it's very possible that she does assist the fashion director. Her title just does not make it clear if these are her own ideas, or if she's just executing the fashion director's ideas.

Does anyone know if she actually creates some of the editorials there? Does anyone have the magazine to check the credits?

I would say that if she is credited as the stylist in the magazine, then she's much more than an assistant. If the Fashion Director is credited ... then, yes ... she's only an assist and and would not have much creative input into the editorials.