Though we’re chasing for an official comment, according to a disgruntled poster over at NeoGAF ModNation Racers fanatics will only be able to share their modding and karting affections with people from the same region.
At least, that’s what a pic of the error message received when trying to invite players from other regions suggests:
Whether or not this constraint was something intentionally introduced to combat lag and the content streaming challenges the game experiences is not fully known. We doubt United Front Games would do this just to piss off the community. We’re also not sure if such a restriction could be lifted in the future through a patch.
Why don’t we just ask UFG? OK, then! We will!
Source: NeoGAF.