So Fairy Lock is still callable via Metronome, even though it's not available on anything. I haven't experienced it myself, but apparently using it crashes the game. Watch out? Accelerock is also in a similar situation (usable but unavailable). Tweets on the topic have only surfaced since the update's dropped, so maybe the move data or metronome logic was changed to make this possible.
I saw this on reddit, so word of the bug has spread pretty quickly. I'm mildly annoyed by the misinformation going around* but it can't be helped. Some pre-patch footage of successful Fairy Lock was found, so I'm fairly sure of my guess about the update. Thanks to the battle mechanics thread we know Accelerock/V-create have animations too. I forgot about Mat Block and Softboiled at the time, but I'm pretty sure those are the only other moves nobody currently ingame learns.
Also found out Night Daze doesn't show the HP drop properly.
*The original snapped move pastebin is only based on the generic description, not the usable move flag