With Midi Wizard you can change the transmitting midi channel of your keyboard and/or transpose it on the fly, simply pressing a button and a key.
Open it in your VST host application, connect the host midi input to the Midi Wizard's midi input and its midi output to the midi input of a VST instrument, then:
Of course, you can use only two buttons of your midi keyboard, sending respectively CC messages #105 and #110 and reset the transmitting channel to "1" and/or the transpose interval to "0" by pressing the C3 key.
You can change the CC messages used by Midi Wizard through the relevant drop lists in its GUI.
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