Captain Toad: Treasure Tracker releases later this week, and we now know how amiibo will work with the game. If you happen to have the Super Mario Odyssey amiibo, you can use them with Captain Toad: Treasure Tracker to immediately unlock the Mario Odyssey levels. As for other amiibo, a Toad amiibo will give you an invincibility mushroom. All of the other amiibo will give you a 1-up mushroom.
You Can Use The Mario Odyssey amiibo To Immediately Unlock Captain Toad: Treasure Tracker’s Mario Odyssey Levels

This was covered in reddit Around June 20.
Huh
||I don’t mind about the amiibo weaponry but i think the best example on how to use them is the data exchange between twilight princess HD and breath of wild via the wolf link amiibo, the other weapons that make use of the amiibo function lack that sense of connectivity and achievement… ||
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What happened to the hidden toad mini game that unlocked with the toad amiibo?