Apparently there's a series of recordings of Franz Schmidt's music for piano left hand on Ad vitam records. No.10, with two of his quintets (the G major for piano left-hand and quartet, the B-flat for clarinet, piano, and string trio, first of two), was released on the thirteenth of this month (https://www.prestomusic.com/classical/products/9382680--schmidt-f-quintets). I know the G major especially well from an issue of Wührer's piano (2-hands)-and strings arrangement (plus Bruckner's string quintet) on London Decca CD awhile back (Vienna Philharmonia Quintet) - very typical Franz Schmidt , with a finale that looks forward to the scherzo-like section of his 4th symphony (though without quite as many call-backs to earlier material).
You can hear the G major in its original left hand version on a 1992 Orfeo disc (C 287 921 A) with Rainer Keuschnig at the piano.
I believe that CD has the same two quintets as here.
Indeed it does. It will be nice to have a recording back in print.