What is the vapor barrier in your stackup made of (foil)?
What is the Dow housewrap made of, if not polyolefin?
If doing it sans plastique, use a double layering of roofing felt as the drain-plane rather than housewrap, and allow at least 10mm of ventilation gap between the lath and felt. DO detail the exteror OSB as a primary air barrier to avoid convection currents between your stucco cavity and the studwall cavities. Roofing felt is lower-perm than most housewraps, higher perm than fan-fold XPS, but becomes more vapor-open at higher humidity, which isn't exactly what you want, still, 2-layer felt has a long & successful history under stucco. With metal lath you have the luxury of making that ventilation cavity pretty deep. Screen the bottom & top vent openings to keep insects from making it home, but DO be sure that it's vented both bottom and top. If there's no real overhang at the top you may need some sort of rain-shield/flashing at the top vents, but even with 10cm of overhanging eave to protect it you can side-vent at the very top without much problem.
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