Anita Patrickson worked with Emma on her last two Harry Potter premieres. Deathly Hallows Part 2 London Premiere, and Deathly Hallows Part 2 NY Premiere.
I tried to transcribe the video but there's a tiny part I surely got wrong.
"Someone like Emma Watson is a really unique fashion case. She really is a stylist dream. She can pull off everything from really classic and vintage to really edgy and she still keeps everything looking incredibly fashion-forward. We chose for Harry Potter, for the two really big gowns, we wanted two really separate and different pieces. The first one we went to a classic princess-y. We used a huge Oscar de la Renta gown for the Premiere in London, and that was "Grace Kelly with a twist". And then for New York we've got a Bottega dress which was a little edgy, a little out there. Something a little different for her, but a completely different style, and it had a little corset, with a big, sort of flowing gold skirt, which was incredible."