For example, Dutch translation is "nl" project, country-specific localizations could be "nl_BE" (unmaintained) and "nl_NL" (requested). Most of the localized messages should be the same for all of these 3 projects. But there is no synchronization between projects, so it would be up to the translators to make changes in all projects, which is not realistic. This is not the first time that country-specific locales are requested but not maintained because of this.

One solution would be to programmatically synchronize locale projects "nl_BE", "nl_NL" with "nl".

Note: Once resolved, the same issue should be opened for PICARD and MOBILE.