It's one of the problems with movie synergy. Prior to the Black Panther movie she really didn't fit in the same mold as Moon Girl or Riri. But the movie version does, and for better or for worse marvel has decided to take elements from the movie version (despite being very different from the comic in a lot of ways) and mixing them with the comic version. It's understandable logic from a marketing standpoint, though writing wise it's fitting a square peg into a round hole.
But that's why I think the mystical elements she has which seperate her from the other two (and T'Challa for that matter) are that much more important.