Quote Originally Posted by DanceLouisDance View Post
Edit: Can i use the same activation key on two different accounts?
No, you cannot.

1) One activation key is only for one account.
The game being installed on your PS4 or windows does not matter. What matters is whether you have a key registered to your FFXIV Mogstation account. If you have FFXIV installed on your PC, only the account that has a windows version of the game registered will be able to log in.

2) You need to buy the game for the platform you want to play in.
If you have the PS4 version registered to your account but not the windows version, you won't be able to play on a windows pc. Same for vice-versa. If you have the windows version registered to your account but not the PS4 version, you won't be able to play on a PS4. If you want to play on both PS4 and windows, you will have to buy and register the keys for both the windows and PS4 version of the game to your account.