I don't know if microtransaction is the right word. They are a paywall. I actually don't mind the Zelda and Link functionality. You're not actually getting anything in the game that is unobtainable without it. I do, however, take issue with the Ganondorf and Wolf Link functionality. My issue with Wolf Link should be obvious, but Ganondorf is just annoying. It's basically gating off a harder difficulty mode behind a $13 paywall, which is a ridiculous as every other Amiibo paywall.
I actually don't mind at all Amiibo that allow you to have access to something that's already in the game a little easier. Ammo, skins, currency, even health is fine if there is a free alternative to those same goods. That's why Mario Maker did it best. Gating content and modes behind the paywall of undesirable physical goods like Amiibo is heinous, though, and Nintendo should be slammed for that. It really is disgusting that it's in any game and that Nintendo is getting away with such bullshit with applause.