Stucco on a Cracked Concrete Wall

Yes, you can remove the existing stucco and install a preformed elastomeric joint material, at least 1/4" or 3/8" i width. Make sure the vertical joint locations are no greater than 12 feet on center and line up with any expansion joints present in the concrete wall. Hopefully those existing wall joints exist! You didn't say. If they don't exist then I recommend that you saw-cut new crack control joints into the existing 12" thick concrete wall....make sure that they're at least D/6 in depth (in your case this would be 2.0 inches, but don't cut through any underlaying rebar!). Thoughly clean-out sall dust and debris from the cracks with high pressure compressed air before applying the new joint filler material. Fill-in these crack control joints with a good quality exterior grade silicon caulk that has superior thermal expansion properties.

I would not recommend covering the newly installed elastomeric joint material because any thermal expansion and contraction of the stucco material (and concrete wall underneath) will cause reflective cracking in the stucco overlay at the new joints and other thermal cracking between the vertical joints.

Make sure you use a good quality latex-based concrete binding agent on the newly roughened concrete surface before applying the new stucco.