This outfit is Madame Pholnaset's knock-off Blue Mage garment that she alleges comes from The New World. And of course, because this is Madame Pholnaset, the outfit is glitzy and over-the-top. ^ ^
So why is Madame Pholnaset doing this? The reason is that she needs new rare and exotic goods to imitate and sell. She used to get by faking items from Ishgard and Doma and few were the wiser, but when trade opened with those city states, and their associated territories, products from those lands became more common. Consumers also became more savvy with regards to authenticity and fair pricing. This cost Madame Pholnaset quite a bit of business so now Madame Pholnaset is peddling counterfeit exotics from The New World.