The Toy Name for the Great and Powerful Trixie is "Lula Moon" ... which basically means that the Toy names have no bearing on what they are called in the show.
I think Big-Macintosh is the only pony outside of the Mane-Six that can be confirmed to have the same name on the toy compared to in the show ... at least among the Pocket-Ponies. In the larger figures, there are also the Princesses, Cheerilee, and the CMC's whom have the correct names.
... at least as far as I know.
We can call her whatever we want, really. Golden Harvest or Carrot Top. (Just not "Carrot Cake", since that is the full name of Mr. Cake, as we all recently learned)