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I am not an HVAC professional, but will give you an interim reply as there are no answers so far.
Short answer is : "No"
Putting a cold air return or any ducting into an exterior wall will be almost impossible because you would have to cut through the sill plate (if it goes down through the floor) or the top plate (if it goes up into the attic), either which will destroy the structural integrity of the wall. All this is assuming you are in a standard type house. Without a floor plan, etc, it is almost impossible to answer this question with any solution.
What ever wall it goes into will have to be non-load bearing. You may have to change it to a floor or ceiling vent, but it will have to be large enough to handle the large amount of air flow. If in the floor, the larger vent will have to be strong enough to hold people walking on it.
Building a "cabinet" against the outside wall that will hold the ducting may be an option, but that is where you need the professional advice about insulating it, etc., and ensuring you are getting a sufficient air exchange.
You do not want the return near an existing outflow vent, or it will just pull that air back in without you getting the benefit of the heating/cooling. As much as possible, you want the heated/cooled air coming out of the vents to go across the most amount of living space before going into the return vent.