For convenience sake I'll just make a 'masterpost' for the Percy Jackson ACEOs
Original series (No Gods):
Percy, Annabeth, Grover, Nico, Rachel, Tyson, Thalia, Clarisse, Silena, Beckendorf, Bianca, Zoë, Quintus&Mrs. O'Leary, Katie, Chris, Luke, Ethan, Stolls, Pollux+Castor, Michael, Lee, Calypso, Blackjack, Malcom, Chiron
Heroes of Olympus:
Leo, Piper, Jason, Reyna
Gods (and similar):
Hades, Hera, Artemis & Apollo, Poseidon, Iris, Athena, Demeter, Hermes, Zeus, Mr.D/Dionysus, Juniper, Persephone, Hestia, Charon, Argus, Prometheus