Would you be willing to answer a few brief questions about PlayStation Forums?
Will Final Fantasy XIV A Realm Reborn work if you got it from game sharing?
Does Final Fantasy XIV A Realm Reborn work if it was was game shared to you?
no it will not work.
to use FFXIV you need to have a Square-Enix account and pay a subscription that is tied to the account. without that, you will only be able to download the game and look at the launcher.