Other known variants
+20Grand SwellChoose 1 of your opponent's Pokémon. This attack does 30 damage to that Pokémon for each Pokémon Tool and Stadium card your opponent has in play. (Don't apply Weakness and Resistance for Benched Pokémon.)
AmnesiaChoose 1 of the Defending Pokémon's attacks. That Pokémon can't use that attack during your opponent's next turn.
A rare Pokémon discovered during a deep-sea exploration. It has not changed in over 100 million years.
If my opponent has Celebi-EX with "Time Recall" in play, can I use Golduck's "Amnesia" attack to prevent the Defending Pokemon from using one of its previous evolution's attacks?
No, you can only use Amnesia on the attacks that are present on the opponent's card at the time of your attack.
If Wooper uses Amnesia on Scyther's Slash, then Scyther retreats for another Pokémon, then that Pokémon [is Switched] for Scyther again, can Scyther use Slash?
Amnesia references the defending Pokemon, when that Pokemon is benched the effect ends.