I don't actually think they should, but I wanted to understand what the general opinion about those sites is.
As a version of an existing site in a specific language would just contain questions that could be asked on that site, should not a proposal for a localized version be closed as duplicate?
The main problem I can see is when there are too proposal of creating a version of an existing SE site in a language different than language; considering the number of SE sites, and the number of existing languages, I think this would soon create a lot of such proposals.