If you want the item to go through Authenticity Guarantee then you have to exclude all of those locations (PO Box, APO/FPO, territories/protectorates, international).
If you don't exclude any locations, only locations that qualify for AG service will see AG on the listing and non-eligible locations will not see AG. You'd ship directly without authentication to locations like PO Boxes if you don't block them.
For trading cards I don't see a "continental US" restriction. Did you read that on the trading cards FAQ? I'm pretty sure it's a restriction for sneakers.
Both buyer and seller must be located in the United States. U.S. territory locations (incl. Puerto Rico and the U.S. Virgin Islands) and armed forces postal locations are not currently covered. Listings that offer only local pickup or items shipped to P.O. Boxes will not be eligible for Authenticity Guarantee.
https://pages.ebay.com/authenticity-guarantee-tradingcards-seller/