Excellent suggetions from lelle and nightwindsonata! The 65 or so Chopin/Godowsky studies, of which 54 were published, are essentials, to my mind.
Marc-André Hamelin's
Triple Étude after Chopin is now the first of his set of 12 Studies in the Minor Keys, he having substituted it for his earlier study in the same key (A minor)
Le vol du bourdon (
The flight of the bumble-bee, after Rimsky-Korsakov); it combines Chopin's three études in A minor (Opp. 10/2 and 25/4 & 25/11). In response to it I was promted to revive (and revise, from memory) my own study initially entitled
Les trois Chopins that likewise treated all three Chopin A minor études; it dated from 1977 but, on discovery that Godowsky had written one such which had not been published, I considered the possibility that it might one day be published and therefore decided to introduce it to the waste-bin (there were no small-scale paper shredderes in those days). The new version is entitled
Étude en forme de Chopin and is apprioriately dedicated to Marc-André; as well as combining material from those three Chopin études, it quotes from many other Chopin études during its course. Copies may be obtained by writing to sorabji.archive@gmail.com and its first page may be viewed, both in ms. and typeset edition, towards the end of the page
https://www.sorabji-archive.co.uk/hinton/scores.php .