I'm spanish user, and my keyboard is special because there are some extra keys that Spaniard keyboard have, but i understand that GPD will not generate different versions of their device based on the keyboard, then i understand that english is the standard and is fine for most people.
i seriously doubt that GPD will generate other variant of their keyboard. simply they will put any functional and common (standard) for reach more people.
Most people know how to use english keyboard even when is not their native language. my case is clear, on english keyboard, we know that ";" is "?", and this way another keys. yes, you must learn to use it this way, but is a quick learning, and well, from windows you can use "alt" + "shift" and switch between the different keyboards you configured on the system.
The fn key, well, considering the keyboard is not balanced, the location of this key may not so critical in my opinion, because will not fix the main problem of the keyboard layout.