Upvote:0
Visa granting decisions lay with the examining consular officer. There is no way for anyone here to accurately answer your specific question.
As a precaution you might wish to include copies of your birth certificate(s) that show both names along with your parents name with your visa paperwork, as likely the Australian consular office will ask for that information to verify the dual name status.
Another aspect that might come into play, are you over 22? If so, then the validity of your Japanese citizenship might be questioned, which may or may not effect the visa decision.
Ultimately, if it were me, I will call the Australian Embassy/Consulate and ask about how they prefer I handle the dual citizenship / dual name aspect. They are by far the best source of info.
Upvote:7
Just tell the truth. Australia is fine with multiple citizenships, so they're not going to care if you declare multiple citizenships or names, but they will definitely care if they ever find out you purposely mislead them. And if you do ever end up applying for permanent residence, they will require so many documents from you that they will most likely find out.
Source: My own children are dual citizens, they too have a different name in their Japanese passport than in their Australian passport, and Australia is fully aware of this but does not care.
Incidentally, the "some odd reason" you (and my kids) are in this situation is that Japanese passports can only be issued in the same family name as their koseki entry, which in turn must be the same as the mother's family name. And if your mother did not legally adopt your father's last name when they got married, it's quite difficult to change it afterwards. You can include parenthetical extra names in the Japanese passport though, so my kids have both their last names listed along the lines of "Tanaka (Smith)".