I guess if you really wanted to you could try to intercept the MIDI stream with Puredata and convert the velocity or note to another CC signal like PeterWolf suggests. I think it's been said that velocity signal is only sent with gate of an active note, so it might only be a discreet value/pulse anyway.
Perhaps one could also connect the drum gates to switch relays controlling disco lights if they were really keen!
Either way, I just don't think this is the right tool for the job?
I don't know much about it but would this help at all?https://www.gearslutz.com/board/electronic-music-instruments-electronic-music-production/760522-small-portable-scratchpad-midi-sequencer.html