Majora's Mask and it's not even a competition.
Good sequels should be loose continuations of a story that mostly stans on their own. MM is the epitome of this. It's very obviously a sequel, as it uses similar gameplay and assets to OoT and the story directly references its predecessor, but it's an entirely new story in a whole new world, with new music, new characters, new enemy, new gameplay mechanics. And the best part is they achieved nothing short of creating a masterpiece in only 8 months.
Tears of the Kingdom, as much as I love it as a game, is a downright terrible sequel as it contains very few references to BotW and the Sheikah tech is completely unimportant and in fact mostly gone entirely, with no explanation. There are very few changes to the world of Hyrule itself, very few new characters, similar side quests, etc. It feels more like extended DLC than a sequel, which tbf is exactly what it started out as.