Hello,
Scrabble has been already proposed many times.
However, the problem goes much beyond the dictionary. As far as I know, rules are different depending on the language.
For example, in French, O and Ö is the same thing; in German it's two different letters and you can't take the one for the other; again in German, you may consider (I don't know) that Ö and OE is the same thing. In French Ö and OE is for sure something different. In Spanish, some combinations like LL are taken as being another special letter that connot be written as LL.
We have also Russian, and I don't know at all how it goes with cyrillic. And so on...
In fact the dictionary wouldn't be the biggest problem, as you can see. It's probably not a problem to get the official scrabble dictionary of a particular language where scrabble is popular (i.e. French, English, Spanish, Italian, German, etc.), or get a reasonably usable dictionary.
Another thing that make me ask some questions is the fact that the game is in a 2D grid. Many people told me for example for Chess, Connect four and even for battleship, that they weren't able to play the game without having the physical board in front of them.
This makes me believe that many people may not have enough spatial representation abilities to play Scrabble correctly. It's harder than those previously mentioned games, as you must check if you have enough space to put your word in, check that there are crossing words and if they make sense...
By the way, do blind people do crosswords alone, i.e. without sighted help ? In braille it seems to be quite hard, isn't it ?