Mozart's '3 Sonates pour le clavecin ou pianoforte' Op.6 are early but mature works showcasing his developing genius for melody and form. They offer a delightful blend of clarity, expressiveness, and playful charm characteristic of the Classical style.
Focus on shaping phrases with natural ebb and flow, and executing ornamentation with clarity and grace.
3 Sonates pour le clavecin ou pianoforte (Op.6) is rated Henle level 6 of 9 — advanced repertoire, roughly ABRSM grades 7–8. In the RCM system it corresponds to about level 9.
You should be comfortable at Henle level 6 — meaning you can already play level 5–6 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 3 Sonates pour le clavecin ou pianoforte (Op.6) lasts about 45 minutes.
3 Sonates pour le clavecin ou pianoforte (Op.6) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.