Isabella Seymour Conway, Viscountess Beauchamp, later Marchioness of Hertford John Hoppner (1758-1810)

The picture has something of this: lid, people, portrait, costume, veil, vintage, fantasy, woman, bonnet, magic, dress, Renaissance, retro, girl, wear, fairy.
Perhaps it’s a painting of a woman in a blue dress with a large hat on her head and a bouquet of flowers in her hand in front of her left hand.