In Japan, you can buy pocket translators. They look sort of like a thin DS, but with a real keyboard where the bottom screen would be. You type the English or Japanese word, and it'll translate it to the other language. I think some will even speak the word for you so you'll know the correct pronunciation. These have been in existance for many years, so I imagine the 3DS has enough CPU power.

I mean, probably, yeah, but it would take *ages* programming what every single word translates to. Really I don't see any point since there are already plenty of great translation apps on mobile devices we can carry around.