If you've been reading these descriptions closely, you'll know that we've already come across a few female characters who just so happen to be 'clones' of their male originals. It's something of a superhero trope, and here's another entry into it with Dani Phantom. She is, as the name suggests, a female clone of Danny Phantom. The original Phantom initially believes that the new girl is his cousin, but she later turns out to be a clone, purpose-built by Vlad Plasmius.
There's a little drama as the heroes try to work out whether Dani is stable enough to be trusted, but once that clears itself up, she's sent out into the world on her own to forge her own superhero destiny. The costume isn't elaborate, and the nature of the cartoon means that it will never win any design awards, but it's different enough from her clone brother's to make her easily identifiable.