You could have a Curtain Wall with invisible frames, so the visible geometry would be just panels. When defining the panels you could specify the thickness of the panels, which would be equal to the depth of the joints, and also the gap between panels, which would be the width of the joints. Then you could just place the Curtain Wall in front of the Wall, and place it on a separate Layer so you can make it visible or hidden, as needed.
AS you may know, you can also simply place am empty Curtain Wall (no pattern), then go to an Elevation, select the Curtain Wall, go to Edit Mode and simply draw the positions of the Frames (invisible Frames, so they would actually define the joints).
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