We'll see.

Now that's debateable. Bayo is stylistically extreme in a way that many find offputting or even downright offensive.

JRPGs aren't a hot genre anymore, but Xenoblade is a known name now with positive associations, and while Splatoon is an unproven IP and lacks dudebro appeal, it at least seems stylistically appealing to the Nintendo crowd.

Neither are going to set the charts on fire, but both will outsell Bayo 2.

I say stuff wierd : What I mean is, I think Splatoon goes too far out of that Nintendo magic area. It just doesn't seem like a Nintendo game. It seems more like a Nickelodeon or Cartoon Network THQ game or something. I'm sure people will think it is fun but it just doesn't seem to have that Nintendo charm like Mario, Zelda, etc. Just an opinion.

What's a "nintendo magic area"? What does it take to "seem like a Nintendo game" if being made by Nintendo isn't enough? What is this "Nintendo charm"? How do you know it has anything to do with how well a game sells? I certainly never heard of anyone looking at games and being like, oh that game doesn't have nintendo charm, not buying! 

No clue. They both have an equal marketing push.

That's a debatable conclusion.  Bayo2 is a spectacle fighter/character action game.  That genre is very niche honestly, the only company still dedicated to them really is Platinum themselves.  Open world RPGs, on the other hand, are pretty hot right now.  So XCX at least has the advantag there.  Splatoon is more of a wildcard in terms of appeal.  It's designed for a Mario Kart type of broad appeal, but I'm not sure if it will achieve that due to potential marketing blunders.

Bayonetta is the same category as God of War, Devil may Cry, Ninja Gaiden, etc (and I would hope that people realize that Bayonetta was popularized because the creator of DMC was behind it). They're not all identical, but definitely are the same type of game. Xenoblade is a JRPG. Those have a narrower market and only 3 franchises sell all that well.

Each will sell 1-1.5 million

A JRPG in name, but has most of the earmarks if a western RPG, character models not withstanding.  It's open world, it's SciFi, the combat is closely related to systems popular in the west, the setting isn't Japanese I culture centric, the game has a player made main protagonist.  All these things help improve its potential appeal in the west.  The JRPG genre's defining trait being the country of origin makes it a bit hazy in terms of judging the selling potential of the whole genre.  IMO,XCX has the *potential* to sell quite well in the west.  It is not a guarantee, but it has the necessary traits to appeal to a large number of people who would not be interested  other RPGs.

Also, those franchises you listed are the biggest character action franchises by far, yet even of those only two have done really well.  GoW peaked with 3 at 4.77mil, DMC back on the PS2 with almost 3mil (been much lower since), but Ninja Gaiden struggles to reach 1mil, having only broken that threshold three times.  The character action genre is about the same in makeup as the JRPG genre:  a small to medium size with a few standout big sellers.  Only the Character Action standouts are smaller than the JRPG standouts.

XCX I expect to land in the 700k-1m range lifetime.

Splatoon is more of a wild card; as a new IP it's unclear whether it will get off the ground. If it doesn't, 700k lifetime. If it does, 2m isn't out of the question. If I had to guess, I'd say it will end up around the million mark.