It might be that these garments represented those worn by a goddess and were only worn by priestesses or women impersonating goddesses. Of course Circe was a goddess and could easily have worn such garb. As an enchantress Circe might have worn nothing, or perhaps some revealing gossamer gown. But clothes are often an indication of status so as a ruler she might have worn the embroidered girdle and vest, and the heavily flounced skirt. Yes she did.
All deities have the power to foretell the future.
She also had the power to transform creatures from one form to another. She was famous for turning men into swine. Could could also purify people and absolve them from a crime. The wand is a long stick with a butterfly at the end, the symbol of transformation. She was probably a priestess of a religion that worshipped pigs.