Most pedalboards will not send Sysex, so this will not benefit everyone.
I’m very interested in this upcoming Sysex documentation, myself. One potential (MIDI) Solution is an Event Processor / Event Processor Plus. I have one mounted comfortably under my ‘board, along with two power supplies and a Quadra-Thru box. Powered by the MIDI stream (not from the H9, without modification).
Convert – for example – a single CC value to trigger the Sysex message. But I believe that the EPP will only send 32 bytes – including the leading / trailing F0 and F7. Not sure yet what the H9 string length requirements are.
I’ve looked into the Midi Solutions Event Processor myself. It looks like it would work in this situation. It’s an expensive solution considering I only need to change the H9 instrument source, but it may be the only option I have. My Boss ES-8 cannot send Sysex messages.