How do string two instruments together and pass midi

Studiowaves

I have a detune instrument that can detune each midi note and want to send it into the second instrument. As an example, a midi note of 65 going in to the first instrument might send a midi out note as 65 or possibly 65.25 if its detuned into the second instrument. Not sure how to setup the midi in and midi out of each instrument to do that?