Hmm...
What you are describing might be something like using a step sequencer
of some sort to write the chords, but instead of having it free running it is advanced
through the steps by playing the MIDI note.
You might be able to achieve
something using the logical editor in programs like Logic and Cubase.
But
traditionally this is what Max/MSP from
Cycling 74 does incredibly well. And for live work, Max for Ableton
Live could be ideal, especially if you add one of the dedicated hardware controllers made
to use with Live.
Definitely worth investigating.
Andy
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When the going gets weird, the Weird turn Pro.