This video's section shows that doing a certain action makes Eevee sad, and it's not poking, because poking angers, not saddens.
What is that action?
This video's section shows that doing a certain action makes Eevee sad, and it's not poking, because poking angers, not saddens.
What is that action?
I think this is "petting":
In Pokémon-Amie and Pokémon Refresh, the player can pet their Pokémon by using the touch screen. Petting a Pokémon increases its affection. Most Pokémon that can be petted have places where they especially like being pet and places where they dislike it. Source
So I think that petting it too much or petting them in places where they dislike it can cause it to be sad.