Ok this is somthing i have to ask becouse i almost rare i can found somebody for complete the pokèdex in the original R/G/B/Y for the vc. But i have a 3DSJ and my intention is buy the opposite version (im my case blu or green) for my japanese console, but is my question: the game are region lock for the trade?
If you don't have CFW, you will only be able to get the language corresponding to your 3DS.
Also, the games trade are regioned lock.
Only Japanese Pokemon can trade with Japanese Pokemon.
edit:
originally, it is possible to trade among European languages,
but VC blocks this, only allowing same language.
(not that they're being racist, it's simply because the original games are too simply and not programmed like that.
International trading only began with Gen III, albeit not fully implemented.
For example, you could trade between English to Japanese, but the full english name won't be displayed on JPN end,
though the data is technically still there.)