Maybe in a sequel.
But as the game is right now, it wouldn't work.
To be fair, I don't really see a sequel coming out soon, if ever. Maybe the console after the NX, but the only reason we've gotten sequels to games up until about a generation ago was to
1. Create more content for it (being the game/series) and still be able to make money so the company/developer doesn't go bankrupt (for obvious reasons).
2. Make an entirely new game while still being able to use an old IP/characters/setting/etc.
1. Because Splatoon's file sizes are so small, there can be tons of content downloaded to one console and still have plenty of room left over. The game can get updated for months, maybe even years, and still not need a sequel because all the content that'd go into a sequel can just be DLC. I'm sure it'll get ported to the NX with better visuals (or something), but a sequel less than 3 years after the game came out seems unlikely.
2. People play the game for it's mechanics, not the characters/setting. I mean, the characters are great, but if Nintendo announced
Splatoon 2: Now We're Platforming Without Guns it just wouldn't sell, at least not to the target audience of dedicated Splatoon players.