Hmm…if Paige committed mass genocide of innocents, including kittens and babies, then sure, I can imagine both Piper and Phoebe eager to exchange her in order to get Prue back at the beginning of season 4.
But seeing as Paige wasn’t a mass kitten murderer or even an assassin like Cole who both Phoebe and Piper accepted, I’m gonna go with a definite no. Piper and Phoebe would not happily exchange Paige in order to get Prue back, whether they knew she was their sister or not.
In Morality Bites, Phoebe was deeply disturbed when she discovered her future self killed a man in revenge. If she can get this shaken up by the reality of killing someone who wasn’t a good person and who actually deserved it, killing Paige to get Prue back would be something like ‘I’ll kill myself first rather than even think about doing something like that’ to Phoebe. She would never go through with it.
As for Piper, she was deeply troubled to learn that the Awakening spell keeping her alive and well resulted in six people close to dying and danger of others being infected and suffering similar fate. These people were not someone she knew yet still, Piper had Phoebe and Prue reverse the spell.
Then there’s this:
Both Piper and Phoebe sacrificed Prue in Apocalypse Not. Before, they were under the impression that once they got Prue back, they would be able to stop the apocalypse. But getting Prue back meant reuniting all the four horsemen and killing the world. Once they figured this out, Piper refused to save Prue. Even if they both were so gung-ho about even helping the Source himself if it meant getting Prue back.
Now moving onto Charmed Again:
I have a hard time believing they both tried every magical way in existence to bring Prue back. It’s also hard to believe a week after Prue’s death, Piper is still trying spells from the Book.
What makes sense to me is that within the first 24 to 48 hours of Prue’s death, both Piper and Phoebe had already tried every spell in the Book. After those failed, they searched for more resurrection methods. But the consequences of those methods would’ve been something like the Awakening spell or much worst.
Already establishing that both Piper and Phoebe don’t have the combined stomachs to do the whole sacrificing innocents for Prue or themselves, they both couldn’t go forward with resurrecting Prue when it required human sacrifice. Phoebe finally gave up, but Piper went back to the Book again, hoping for a last minute miracle before Prue’s funeral.
Which doesn’t happen.
As grief-stricken and angry Piper may have been, I just can’t see the possibility of her suddenly tossing her head back and screaming to the heavens: ‘Hell yes I sacrifice Paige! Take this half-breed and half-sister I never wanted! Give me my sister and best friend Prue back! Right now dammit!’
Same goes for Phoebe.
Now while I can’t ever see the possibility of Piper and Phoebe ever exchanging Paige for Prue, I do however accept this possibility in that parallel evil world.
That world isn’t totally 100 percent in sync with the real world and every character’s counterpart speaking the exact same dialogues(except replace good with evil). Darryl was cheating on Sheila and having fun at Evil Piper’s strip club. In the other world, the real Darryl wouldn’t be getting a lap dance from a stripper, but doing something completely different.
And I’m pretty sure Gideon and Phoebe had something going on in that evil world as well as Gideon kept giving Phoebe weird looks and touching her every chance he got
Keeping those icky things in mind, I can totally buy Evil Piper and Evil Phoebe doing whatever it took to get Evil Prue back. Including sacrificing innocents and even trying to kill Evil Paige and exchange her for Prue.
