The Pinterest page where I found this notes, “...Marie-Joséphine pointing to a bust of her husband, King Louis XVIII of France, with a portrait of her father, Victor Amadeus III of Sardinia, while reading and with a mandolin and music set aside."
Upgrade image posted 24 September 2018 from pinterest.com-stefanogarbin12-ritratti-1700/. Also posted to the Subalbum for Comtesse de Provence, Maria Giuseppina Luigia di Savoia here.
Compare the Comtesse de Provence's dress and even the setting with those of her sister, the Princesse de Lamballe's d'Agoty portrait. She may be wearing a sheer jacket edged with ruching.
Keywords: 1777, d'Agoty, Maria Giuseppina Luigia, Maria Giuseppa Luisa Benedetta di Savoia, Maria Giuseppina di Savoia, comtesse de Provence, Savoia family, Bourbon family, Princess, Countess, French, high straight coiffure, feathered floral ribboned headdress, necklace, ruched jacket, fitted bodice, ruffled modesty piece, square neckline, bows, stomacher, elbow length sleeves, engageantes, vee waistline, panniers, jeweled over-skirt, puffed cloth ornaments, jeweled under-skirt, shoes