These pieces are arrangements based on Offenbach's operetta 'La Grande-Duchesse de Gérolstein,' likely written in a virtuoso piano style. They would showcase melodic themes from the opera with brilliant passagework and embellishments.
The primary challenge lies in navigating the rapid figurations and stylistic ornamentation with clarity and panache.
2 Bouquets de mélodies sur 'La Grande-Duchesse de Gérolstein' is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
2 Bouquets de mélodies sur 'La Grande-Duchesse de Gérolstein' is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.