I dont think xenoblade x (and mgs 5 although you can say other mgs games are its sequels) count since rather than just having sequel teases they just end without answering most of the questions raised by the story.And the way Xenoblade X endsleaves the story VERY open for a continuation in that exact planet right from where it's left, but mechanically-wise it'd make more sense to do a new world if they go back to X someday. That planet has already been explored.
xenoblade x ending without any explanation for the planet, translation, lucifer backwards, why they are alive without the lifehold, why elma is an alien, why the earth was destroyed, ETC REALLY didnt sit well with me at all since the main story doesnt have much going on in it for an 100 hour game.