I have a daughter who falls dead in the middle of that age group and she loved the movie and she loved Rey but she is still asking for Monster High dolls and HP stuff. It isn't just the gender of the character that matters but by an large little girls play with different toys that little boys do. Boys are much more likely to play with action figures and Legos while girls paly more with fashion dolls. I don't see this movie changing that. I think where it will cross over is things like posters and clothes. I spend less time around boys that age but when I go to her school Jurassic World and The Avengers still reign supreme.
I know it is a small sample but at least among my daughter and her friends I see very little demand for the new SW stuff compared Harry Potter and Peter Jackson. They liked the movie but I don't think it captured a generation like the first series or even Mr HP and I don't think it will change the toy market.