[Well, then that's all he needs to know. (The name, really, was just a curiosity. He didn't have to know it, but when faced with stubbornness, he can be just as bullheaded back.)]

Very well. Then you shall appear to others as nothing more than a beggar. Clothed in rags, a miserable-looking fate placed upon you. None shall look at you, because no one will want anything to do with you; you will be, so to speak, invisible.

[There's no fancy incantation or even Ardyn waving a hand. There is only a bend in the pressure of the air, a buzzing, a feeling like one's ears may pop. A shift, and suddenly, to everyone around, she will appear to be as Ardyn stated. A beggar.]

There. Now, go eavesdrop like only a beggar can.