I know this is absolutely not viable, but...

Ambipom @ Heavy-Duty Boots
Ability: Technician
Tera Type: Normal
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Triple Axel
- Double Hit
- U-turn
- Knock Off
Imagine. The Cornerpon user sees an Ambipom on the other team. They laugh.
What idiot uses an Ambipom?
They play, expecting an easy victory. In the middle of the battle, the two Glowkings pivot out with Chilly reception. Cornerpon user's Glowking managed to "lose"the speed tie, and they see Ambipom switch in. They burst into laughter.
Free set-up for Cornerpon? Cornerpon sweep?
And then they switch in, expecting a free SD, then a sweep. Then...
Ambipom used Triple Axel!
21%!
42%!
37%!
It's supereffective!
Ogerpon-Cornerstone fainted!
They will rue the day they laughed at the Ambipom.

252 Atk Technician Ambipom Triple Axel (120 BP) (3 hits) vs. 0 HP / 0 Def Ogerpon-Cornerstone: 380-450 (126.2 - 149.5%) -- guaranteed OHKO