I discovered theres a CHORD LOOPER file editor MIDIKit tech available for Mac OSX that can edit chord looper files in a limited way.
Give your support to the developer to consider making a seperate app that has a BIAB/iRealPro type GUI just for chord looper stuff on his forum.
Here is there original post in the PSR SX 900 section ( as CHORD LOOPER feature was first - and is more fully - supported on the SX 700/900 than Genos )
https://www.psrtutorial.com/forum/index.php/topic,64604.0.html