Honestly, I'm really doubtful of Xenoblade, personally. ARMS and Pokemon both have an evergreen nature to them that makes them easier to sell over time; Xenoblade 2 and other more niche JRPGs usually sell what they're gonna sell in around a month or two and then fall off, and they don't really get revived in the same way games like ARMS and Pokemon do twith their marketing. I'm not sure Nintendo will want to try and bring it back when most people who were interested most likely bought it and Xenoblade Chronicles Remastered has taken the Xenoblade spotlight ATM.
ARMS is a Nintendo mutltiplayer game, and those always keep their staying power thanks to people just really liking Nintendo's multiplayer. Sure, it's not a huge mega seller, but despite what a lot of people say, it did alright for itself and was always poised for a comeback. I think Min Min in Smash will definitely help in making ARMS 2 a reality at some point down the road, probably on the Switch's successor.
Pokemon is...Well, Pokemon. It breaks a lot of our precedents and patterns however it well dang pleases 'cause most of the time it gets a character, it's because Nintendo and TPC did it just to flaunt it some more. It in my personal opinion is probably the best shot out of any Nintendo newcomer right now because it'd be an easy get, and promotes a product that will keep selling throughout the Switch's life. I could easily see a Gen 8 'Mon sneaking in come CP10 or 11.