CTNC
Living Tree
You'd think that'd be a hard question, but no. It's very easy. It's either Supersonic or Confuse Ray.Remixing this question from earlier...
<To Climmy and you> What has to be your least favorite status effect-inflicting move? Similarly, what has to be your least favorite move to use in battle?
Both moves cause confusion. It sounds like it'd be good because confusion can affect any type of Pokemon, but it only lasts 1-3 Turns (2-4 if you count the turn you snap out of confusion) and while confused there's a 1/3 chance of the Pokemon hurting itself. Even the confusion causing move doesn't miss, it's still likely to do nothing. It's a 1/2 chance in games before Sun and Moon, but I still think is bad when averages to 1 time hurting themself per time confused. The only time I like using confusion is when the Pokemon has already used their useful moves and has nothing better to do.
Supersonic has 55 Accuracy. Thankfully the only Pokemon I've had to use it with is Butterfree and their Ability, Compound Eyes, boosts accuracy by 30% to a still bad 71.5 Accuracy. Confuse Ray has 100 Accuracy, but it somehow got a TM. (For those who don't play Pokemon: TMs teach moves.) I don't know what's worse, that Confuse Ray has a TM in Scarlet and Violet or that I used it. Armorouge didn't have any other moves worth teaching.
Supersonic.
Let me tell you about Picknicer Alicia. She had 2 Bellsprout, 2 Oddish, and a line of sight that's let her see every trainer that tried to cross Route 9. 4 Grass/Poison Pokemon and no way to avoid her challenge. My team was just Ivysaur's and Butterfree back then. Ivysaur couldn't help because Poison types are immune to Poison Powder and Grass Types are immune to Leech Seed. That left Butterfree's Supersonic, and she was only able to use enough Supersonics for 2 Pokemon to KO themselves. Thankfuly both Oddish knew Sweet Scent, Poison Powder, Stun Spore, and Sleep Powder. Ivysaur didn't care and Butterfree wouldn't be able to be poisoned after Stun Spore, so we could wait until Struggle. Supersonic was used for the Bellsprout and we were barely able to win. If we'd gotten unlucky, we would have had needed a rematch.
(One interesting thing with Status Moves only is how some random trainers become tougher than any boss. I will never forget Alicia.)