Much simpler than that.
A user that wants to join the game define his language.
From that moment he will have every page on that language, so I guess he will not have reason to lie...
Now, the game will set him a BB-league, that is dedicated for his language.
Meaning, in case he wants to be a "English (USA) user", he will find (for example) one of the X different English (USA) speaking BB-nation, and set him to one of their leagues.
i play this game in 3 languages(english(UK), german and german(austria)), and in the begining i prefered english(UK) over the US version.
To make it impossible to change language, especially unseend of the language versions would be really bad in my eyes.
What wouldn't you understand?
It is all about BB?
In addiution, it will open conversation between different Real-nation, that I find it a blessing in any case.
i couldn#t communicate with russian users for example. In germany we have a good scouting system, which is mentoring player with young talents and helping them where they can(and scouts usually take care of groups like 20yo guards so that they know the other existing talents). Now you have to talk to greek, russian, french and german user at one time since you couldn't expect them to speak all languages.
And i am pretty sure, that the gloves team make the same in your country ;)
Not all BB users will find a language to communciate which each other, and it will be always more comfortable in there own language. And those who can or enjoy it, i believe already communicate here across the borders, also through the NT competion(i talked a lot to the glove and rwystyrk through that, and we still chat from time to time).