Nintendo has published guidelines on how to run #tournaments. I haven't read any of it, so I can't give you a summary, but this could potentially be pretty bad (I'm assuming the worst considering what's happening in the past with the #SuperSmashBros community).
So, for tournaments which have over 300 participants (online, for offline tournaments, it is 200) WILL need to gain permission from Nintendo to be able to host.
Does this mean that a Donkey Kong tournament will be treated this way too? Or Popeye?
Nintendo's treatment of their fans never stops amazing me. At the same time, it appears to only affect Japan (to my understanding). Perhaps the solution is that all huge unlicensed Nintendo tournaments are held in Shanghai instead :)