This work by Noren is a late-romantic piano piece that explores more chromatic harmonic textures. It is noted for its sophisticated use of pedal to create a lush, dream-like environment.
The technical difficulty lies in the sustained voicing required to maintain the lyrical line through chromatic textures.
Comparable difficulty and character — good candidates for what to learn next.
Berceuse (Op.12) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
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 Berceuse (Op.12) lasts about 4 minutes.
Berceuse (Op.12) 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 Calmes, aux quais déserts by Joseph Jongen, Calmes, aux quais déserts by Joseph Jongen, Gymnopédie No. 1 by Erik Satie — see the full similar-pieces list on this page.