Xenoblade is the first series that comes to mind.

Splatoon I put nearly as much time, which given I am well over 500 hours in both Xenoblade combined is to Splatoons credit, but if I had to say honestly, it is still Xenoblade Chronicles.

Shout out to ARMS though, haven't played that one yet but likely will get it somewhere down the line.

Xenoblade; the original was one of the best games of the 7th generation in my opinion, and while XCX wasn't quite as great, it was still an impressive achievement.

Splatoon is excellent too, and I did enjoy it thoroughly, but as I'm not into online multiplayer, it didn't offer quite as much bang for my buck.

ARMS I can appreciate for what it is, but I'm just not into fighting games so it's not my cup of tea.

Smash Bros for me

Smash Bros started 18 years ago, not in the last 10.

Xenoblade and Splatoon are tied. This is interesting

Uh no. The wars series goes back far, FARTHER than fire emblem famicom wars came out in 1988 and FE1 came out in 1990.

New IPs... its split between xenoblade and splattoon, but does xenoblade even count? The xeno series existed for longer than 10 years I think...

I vote for Xenoblade even though I have only played the first game.

Despite the similarities in name, developers and genre, the Xeno series is not all the same IP.  Xenogears is owned by Square, Xenosaga is owned by Namco and Xenoblade is owned by Nintendo.  So it's fair to call Xenoblade a new franchise with obvious spiritual predecessors.

I'll go with Splatoon. Normally, I don't like shooters at all, but Nintendo managed to make one that I find to be very creative and fun. The mechanic of hiding and traversing in ink is a very cool and innovative idea.