I see. Thanks for all the info so far! This is really interesting.
I took a look at my Wario Land II box, and although the cart clearly says EUR in its code, the top of the box says "Scandinavia: imported by, Bergsala AB, Kungsbacka, Sweden". So I guess even though the cart has a general code, this is actually a Scandinavian copy.
My Wario Land copies, one of which is UKV and the other is EUR, actually have some other differences in the stickers that I noticed. Here's a picture:
As you can see, the entire graphic is higher up on the UKV one, and a little more to the right as well. The Nintendo seal is also lower down and the "Original Game Boy Pak" logo is bigger on UKV.
This kind of stuff is really interesting to me. Does anyone have any more info on this, or maybe any theories about why something like that would get changed?