Johann Baptist Cramer's Op. 7 sonatas are significant pedagogical works that bridge the Classical and early Romantic eras. They offer a blend of technical challenges and musical expressiveness.
Emphasize singing melodic lines and balanced voicing between hands.
3 Piano Sonatas (Op.7) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 5.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 Piano Sonatas (Op.7) lasts about 14 minutes.
3 Piano Sonatas (Op.7) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.