Dress: Silk Evening Dress by Alexander McQueen (not exact color)(thanks @audreyhopestyle)
Audrey Hope (played by Emily Alyn Lind) on Gossip Girl on HBO Max was spotted wearing this purple gown on Gossip Girl on episode 'Great Reputations' (2x03) in Dec 2022. Audrey's Dress is the Silk Evening Dress by Alexander McQueen .