Actually I dont think i would have minded that explanation all that much... and over in Marvel, under Robinson, this was actually the plot surrounding Warrior Woman, who turned out to be the Squadron Sinister (bad) version hiding among Squadron Supreme (good) versions of her colleagues... untill she turned on them, and is now being stalked by her good counterpart.
I dont know if it's just me, but why do I keep thinking of the E-3 versions of the Wonder Family of characters as stuff of parents nightmares? Like 'we' (me) have this image that every parent would be proud to have girls like Diana, Donna and Cassandra... but that their E-3 versions would be these horrid brats in Harley Quinn's movie wardrobe?