You don't need to do anything about l10n issues, it gets done automatically. Or rather, after you finished one article, some translation tags need to be added to it, to make it translatable.
Just ping us once done (you can also do that on #kde-www on freenode), and we can do it.
If the category already referres to them as widgets then you should use that term to keep consistency. And AFAIK plasmoid is the more technical term.