Yes... only one person needs to own the game. You must be logged in on your Japanese account in order for shareplay for this specific game to work. A friend of mines ( who opted to buy the digital copy thursday nov 26) was on his American psn account and I ( waiting on hard copy to arrive Monday, was curious in wanting to try out the game) was on my American psn account. In our first attempt to shareplay ... a prompt message appeared stating that shareplay would not work because xxxx game has not released in your country etc etc. So I logged in on my Japanese psn account and the shareplay worked.I was able to try out training mode, characters, fight vs him , etc .. literally full access to everything. So as long as the person who owns the game is a playstation plus member he can shareplay as long as the other person is on their Japanese account.