I was thinking about what these greats that are known more for their orchestral works wrote for piano including Chamber music with piano? (if indeed they did)
I know of 3 piano sonatas by Wagner (the Bb is appauling!!!)
a sonata by Respighi
2 concerto-type pieces by R.Strauss (burleske and 2 LH works) and the sonata
people like Borodin, Glinka, Puccini, Verdi, Respighi, Britten, Vaughan-Williams (I know of a piano concerto from the last 2 and a LH by Britten as well), Elgar, Rossini, Mahler, Holst, Kodaly
yah get the idea...