Hacking Different firmwares playing with each other

[JohnathanWhiteKnight]

I looked on google for a few seconds and couldn't find an answer, I hope this is accepted. Can 3DS's with different firmwares play with each other, games like animal crossing? I want to get cfw and cool shops on my 3ds but don't want the person I play with to turn in to a crazy pirate as they are too young for that

 

[Hunter]

as long as they are the same region, there should not be a problem between cfw and ofw playing with each other