If you have the midi chord track on the same track in each SGU you can solo it and it will just save the the midi chord track with the SGU file name.
To use the Biab Midi Batch convert you will need to save all SGU with the midi chord track soloed, you could get AutoHotkey to do this.

It depends on how soon you need this, if you don't want to wait a year or more or never for PG then it is something that can be looked at.

I did make an AHK script to batch save all the Midi RealChart Drums to files.

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