Hacking 3DS region unlock firmware 8.1

[Bluecow]

I'am sorry if this question has already been posted somewhere here or this thread belongs somewhere else, but i'am very new to the homebrew scene.
I have a european 3DS and ordered the new pokemon mystery dungeon game in the US, now I have to unlock the region of my 3DS, which is currently running on version 8.1 can somebody tell me what is the simplest way to unlock the region of my 3ds, hopefully without having to buy another game or a flashcard.
Thanks for the help

 

[kumorebikun]

Since you're on 8.1 the best way to do it would be to install rxTools on your 3ds, this link is really easy to follow:

https://gbatemp.net/threads/tutorial-installing-rxtools-custom-firmware-3ds-and-2ds.390867/

After you completed the set up process the game from the US should run on your 3DS.