Get in line with the thousands of other Americans who want to do the exact same thing as you. By the way, that line is preceded by another line of about a million Japanese boys who also want to work as video game programmers, and don't require visa sponsorship for the purpose.
Let's add to this list, graphic designer (unless you are designing things particular to your actual demographic, meaning, you bring to the table something the Japanese do not...)* Anime animator, manga writer, designer, etcetera etcetera etcetera...
Basuotoko makes a very good point, you're in line behind thousands of other Non-Japanese who want to do these things, but more importantly, also behind many many more Japanese who want to do the same, and will edge you out just for being Japanese... think that's racist? It's not, it's just that what a Japanese boy learns of Japanese society in 21 years, takes you perhaps, 25, from the
time you get there...
There's no payoff to hiring gaijin workers. A) It's taking away work that a Japanese person could do, B) theres no expectation that you understand or even comply with Japanese business etiquette, and most importantly C) there are probably very very few people who understand marketing to the Japanese, I can think of only one prominent person off the top of my head.
Like Ewok, and I had said earlier, your best bet is to work for Nintendo America, you won't go into Nintendo Japan green... Learn Japanese, perhaps you can get a job translating, though that might be taken by English literate native Japanese.
I think there is a way in the door, but it might not be doing exactly what you want to do... there is a strategy, and you have to learn it.
*I'd say it would be easier to do product design, than graphic design, even my ex misspelled something on a KFC advert, do you think you'll fare better there... you just have to design things that are interesting in and of themselves... not shiny robots... Japan has enough of that already.
When everyone is painting landscapes... paint portraits.