Chest Hunt: Inazuma City
I love this city. I also missed at least one chest here. I'll be making a missed chest video for all of this island, but if you want to get the chest now instead of waiting, its from completing the Temaria game on a little island located here: https://imgur.com/XXXmkfc
If you've not unlocked the Temaria game, it can be unlocked just outside of Inazuma city by completing the quest "Temaria Game".