FEM!PERCY JACKSON X MARAUDERS

What if there was a fifth Marauders? What if it was a girl ? What if it was Percy? What if Percy was actually British ? What if her real last name was Potter? What if she is James Potters older sister? What if she attended Ivellemory instead of Hogwarts because of camp? What if she shifts back to Hogwarts after the wars?
What if she falls for her brothers best friend?