It does not matter, in this case you're not breaking any sort of copyright law or anything regarding the DMCA. You are not creating a "game server." Ok, technically one of the Nintendo Switches has to Host the LAN game, so yes, that's creating a game server, but that's one that Nintendo programmed into the game, you're not stealing code or anything like that. This wouldn't even required CFW or any other mods to the Switch, you just need a LAN adapter and a way of linking it to a VPN.
All you are doing is using the internet to bridge multiple network connections together, basically as if you had an extremely long ethernet cable going from your house to your friend's house. This doesn't break anything in the DMCA, no matter what console or game it is.
Now, what they could go against is if you tried to recreate their $20 a month service, but that would be an extremely difficult thing to do, we'd have to break SSL encryption and study the protocols the games use, and re-implement things like matchmaking. You'd basically be making Wiimmfi for Nintendo Switch. I'm not suggesting anything close to that.
Those sorts of terms in the DMCA are more geared toward if you were to make your own private server for games like World of Warcraft or Runescape. In this case you're not putting up a game server at all, you're putting up a VPN server and using it to link networks together, networks that just so happen to have Nintendo Switches on them.