All I can find out about her is that she married in 1777.
Dorotheum's English language note follows, "Anne Catherine Le Preudhomme de Chatenoy married Jean Jacques Marie, Comte de Verdun in 1777, a rich member of the influential circle of the Comte d’Artois, brother of King Louis XVI. In her account book Madame Vigée Lebrun noted several portraits of her friend, painted in 1776, 1779, 1780 and 1782. The later ones are probably autograph replicas of the original painting, executed in 1776 which has as yet to be identified. It is probable that our painting is one of the later versions and was painted in 1780 or 1782. Some unimportant parts of the painting could have been executed by a collaborator in Vigée Lebrun´s studio as was usual practice from 1780 onwards, as the artist was very busy. Some of the most famous works of Vigée Lebrun are autograph replicas, for example, her famous self-portrait in the National Gallery, London, is a replica after the primary version in a Swiss private collection.