So I've got my first Supreme Emblem after beating Apotheosis (the secret path) a while ago. Since then, its been in my inventory as a personal trophy. While you can get another by reaching 99999 Renowns (which I haven't), it sounds reasonable to sell one of them for extra golds, though grinding isn't an issue in post-game.
Anyways just for the sake of curiosity, what do you do with them?