Not widely accepted at all, as both nations are Constitutional Monarchies. Japan's head of State is the Emperor of Japan (note: "Imperial Japan" or "Japanese Empire" strictly refer to the period of the Meiji Restoration (1868?) up until V-J Day (1945), a time period where the Emperor had arguably the most political power at any point in history. In fact, for the vast period of documented history, the Emperor of Japan had very little in the way of actual authority and typically the "head of government" was either a military commander (the Shogunate, The military Occupation under General MacArthur) or the Prime Minister of the Diet (present period).).
The Head of State of Austrailia is Queen Elizabeth II (the same one who is Queen of the UK... as well as Canada, New Zealand, and some small independent island nations that were formally colonies of Great Britain). The day to day functions of the Monarch in all nations that still recognize her as the Head of State are performed by the "Governor General" of that nation, which is determined by each nation's constitution (except New Zealand, which does not have a codified constitution). Most of the formal political powers of Govenor Generals are quite limited and they are not executives at all (in less serious answers, I like to refer to their primary duty as "Keep the Throne Warm for the Queen". Mostly when I'm with citizens of the nation and feel like getting my republican on (not a political party... just opposition to monarchs).
Germany is a Parlimentary Republic in that the elected head of state (President of Germany) has very little in the way of actual political power, much in the way that the Queen of England (and all that other stuff) does... the Germans merely have the ability to put the next one in office before the current one dies.
France is a Semi-Presidential Republic due to the fact that the President of France does have executive powers when his/her party makes the majority in the legislature... but is only Head of State if this is not the case (and it rarely is).