Hi Nicolas,
In the case of Portugal, we have been using lists of officially proposed monuments for WLM since 2011, as they are generally valuable cultural heritage and notable buildings, and we see a great opportunity to document them, even if they don't gather any official protection (unless they are destroyed, of course).
Paulo
Yes, of course, we do the same in France (and in fact, we even have monuments that are not even proposed of protection). As long as there is a list somewhere, no problem for WLM.
I just asked for the import on Wikidata ;)
Cdlt, ~nicolas