x2
-20BlindsideDoes 50 damage to 1 of your opponent's Pokémon that has any damage counters on it. (Don't apply Weakness and Resistance for Benched Pokémon.)
PunishmentIf the Defending Pokémon is a Stage 2 Pokémon, this attack does 60 more damage.
Can Cramorant with the "Lost Provisions" Ability use an attack from a Technical Machine such as TM:Blindside for no energy cost if there are 4 cards in the Lost Zone?
Yes, that will work.
For Mandibuzz's "Blindside" attack, who chooses which of the opponent's Pokemon receives the damage?
The attacking player chooses which of the opponent's Pokemon receives damage from the attack, but remember the opponent's Pokemon must already have damage counters on it first.