Madame Charles Simon Favart (Marie Justine Benoîte Duronceray, 1727–1772) Francois-Hubert Drouais (1727-1775)

The picture has something of this: piano, people, music, wear, musician, pianist, child, portrait, woman, indoors, instrument, facial expression, opera, book bindings, classical music, girl, furniture.
Perhaps it’s a painting of a woman in a blue dress sitting at a piano with a sheet of music in front of her and a book.