I feel that the glitch doesn't apply specifically to amiibo villagers anymore but it can happen with ANY villager.
Now, I don't know if it's random or if it's a specific in-game action that determines this as many are obviously still trading without issues.
I'm really hoping that with the Bunny Event ending today, we will get a patch soon as I've been worried about adoptions.
Yeah from what I'm hearing >_< I have a feeling they'll probably wait until Earth Day to fix it because that's when the next patch will be released but I could be wrong.