The most upvoted answer gives the explanation the ball manufacturer is Swedish ('axe' in Swedish starts with a 'y'), but other answers say it was probably manufactured in a country where English wasn't the first language (e.g. China) and the 'y' for axe was simply a typo.
The evidence against the Swedish explanation is that the ball says c for 'cat' and d for 'dog', but in swedish the translations are 'katt' and 'hund' respectively.
This may be a case where the most upvoted answer is likely wrong, but because it was so entertaining and took so much effort, it was upvoted much more than the boring (but probably correct) answer.
EDIT: I had only skimmed the most upvoted answer, it does indeed trace the ball's manufacture to China and suggest the 'y for axe' is a typo. Apologies for the confusion.
The most upvoted answer doesn't say that it's a Swedish designed ball, rather that it is a Chinese knockoff where they moved things around and replaced some of the symbols with ones from books/toys for Swedish kids.
Hence why the ones that match the 'official' ball make sense in English but the ones that don't make more sense in Swedish.
Is there also a Swedish version of the ball? In that case I have a possible explanation.
When the ball was copied, they may have worked from images. You need more than one image because the ball is round.
Could the copycat have used an English version for one of the sides, and Swedish for the other? By looking at the images and letters around the Y, they actually make more sense in Swedish
The poster may have made a mistake by interpreting the "W" for "worm". If the Swedish theory is right, it is actually an "M" as worm is translated to "mask" in Swedish. They also seem unaware that a picature of the nail can also be translated as "nagel".
E - Elefant
N - Nagel
M - Mask / Metmask
K - Känguru
To me it looks like that side fits the Swedish words perfectly. The "Q" (queen) is copied from a different picture that comes from the English version
Edit: One of the comments on Stack exchange seems to suggest the same theory. The symbols seem to be a mix of at least two different sources.
It's clearly not properly designed to be for swedish, this is noted in the reply, apart from some letters being off, it lacks åäö. But it's still not clear why they would use "u-boat" for u. While apparently correct english (never heard it), it being Swedish ubåt seems higher likelihood to me.
I'm wondering if they might have combined mixed two designs, as a lot of the letters works in both. Maybe they looked at two pictures and didn't realise one was for another language? It seems possible to me that they'd design the ball based on product pictures, and those are often not showing all angles of a product.
That's not a "nowadays" thing. That has always been the meaning of U-boat; it was an explicit propaganda goal to use different words for German submarines and American ones.
The evidence against the Swedish explanation is that the ball says c for 'cat' and d for 'dog', but in swedish the translations are 'katt' and 'hund' respectively.
This may be a case where the most upvoted answer is likely wrong, but because it was so entertaining and took so much effort, it was upvoted much more than the boring (but probably correct) answer.
EDIT: I had only skimmed the most upvoted answer, it does indeed trace the ball's manufacture to China and suggest the 'y for axe' is a typo. Apologies for the confusion.