unless either of those lets you send the same notes on multiple midi channels at once, no

Hi I'm trying play the 4 channels of the mgb at once on the Gameboy original. Does anyone know if this is possible? I'm using a keystep and an mpc it seems like I should be able to figure this out but I can't. I'm wanting to explore the different tibres I can create by messing with all the channels at once ( not playing multiple notes at the same time ). I'm able to make a loop with the mpc and have the the 4 channels play back like this but I'd like to be able to do something live.