I'd say she could also be that first hero we saw. The resemblance and clues towards Jelly are sort of obvious enough that it might be a red herring sort of deal, as some of you have suggested already. If so, this one might have been that female hero we never saw out of the transformation/costume, and Jelly's resemblance is because they're related or something. I'm leaning more towards her being Jelly though.