About: "This game has region lock?"
I think actually we don't have this. But, I don't recommend you to play it right now (if buy the game somehow), because the game's server actually is new, and is still being improved. Even for us (in Brazil), the ping is not the best. But, as I said, they are working on it.
I'm really happy to see you found the game. The in game language is english, so, you'll have an easy time playing later.
About the possibility to buy the game from another country, these are the users who can probably give you a official answer (https://profa.ne/forum/groups/administrators). Just wait a bit.