This is a variant title or printing for the Paul Barbot fantasy on 'La Sonnambula'. Like its counterpart, it prioritizes virtuosic display of Bellinian melodies through keyboard-heavy figurations.
At Henle 5 this is a late-intermediate piece — technically substantial, with musical demands to match. The main demands: fast passage work that stays light and even at tempo; sweeping arpeggio figures that must stay smooth across positions; and ornaments that need to sound effortless, not squeezed in.
Beyond that, expect a waltz lilt that needs charm and a flexible left hand.
Focus on the evenness of the scale passages that bridge the thematic sections.
Comparable difficulty and character — good candidates for what to learn next.
A level or two down with the same spirit — ideal if this piece is still out of reach.
Where this piece's skills lead: slightly harder works making similar technical demands.
Fantaisie sur un thême célèbre de 'La sonnambule' (Op.47) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 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.
A typical performance of Fantaisie sur un thême célèbre de 'La sonnambule' (Op.47) lasts about 7 minutes.
Fantaisie sur un thême célèbre de 'La sonnambule' (Op.47) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include Fantaisie sur un thême célèbre de 'La sonnambula' by Paul Barbot, Bonheur perdu by Paul Barbot, 10 Variations on "Unser dummer Pöbel meint" for Piano in G Major by Wolfgang Amadeus Mozart — see the full similar-pieces list on this page.