https://bugzilla.wikimedia.org/show_bug.cgi?id=73534
--- Comment #4 from Fabian CommodoreFabianus@gmx.de --- Okay I'm checking the source code about the support for 'from_url'. It currently supports all pages which uses the "<code>.url" scheme which vikidia is not following.
But otherwise it should be possible to just add an entry 'de' to the langs dictionary of vikidata.
It also appears that the wowwiki family also needs to be checked if they support 'from_url'.