real-time sustain (MIDI out, play sound restrictions)

Hello,

I observe that Musescore doesn't cope with the sustain pedal I press from a MIDI controller.
Giving the seeming unavailability of any real-time sustain effect and, as someone else turned out to be somewhat justly reasoned while bringing up this same issue, namely that it wouldn't extend to Musescore's primary goal and that there's several obvious way-outs which I too hold to be the case. I went on thus:

Since I want to record, hear the recording, as well as the record
I keep the Musescore MIDI enable for the note input,
and I make the keys sound off on garageband which leads me to naturally bring Musescore audio-out down to nil.
The hitch here is that there's of course nothing more to be heard when I try to run the playback.
Could I restrain Musescore audio to the playback only? or else?

Some will say "use the JACK server thingy.." but it seems to disable the Midi-in, plus I merely use a controller. To make it plain, my attempt is to set up Musescore so that it process the MIDI-IN for composing, and have it concurrently sent on some kind of virtual MIDI-OUT port. (to which extent I mean the editing, real-time, and playback sound data altogether).

Hope I've been clear enough,
Looking forward your assistance.