Just FYI - this isn't Hideo. I can set mine to say OLD SNAKE right now.
It works for any Japanese account but has been disabled for other regions.
In your JPN account, just go to edit profile, and you can set your handle to be different from your account name (and I don't mean your email address - I mean your PSN name) and after you've been added as a friend by someone - the chosen handle will display instead of your PSN name.
Not all games support the displaying of the handle instead of the account name but some do.