My guide for the E4/Pokémon meta discussion hub

Well, does Eduard have that? No. Also, if you have to, Sash and Hone Claws Hustle gives you this:

+1 0 Atk Hustle Scyther Ice Shard vs. 0 HP / 0 Def Garchomp: 436-520 (122.1 - 145.6%) – guaranteed OHKO

Neutral Nature, no investment in attack, just Hustle and a Hone Claws. My setup is here:
Scyther
Bashful Nature
Ability: Hustle
EVs:

  • Ice Shard
    (Typing is Ice Fighting)

Garchomp @ Rockium Z
Jolly Nature
Ability: Rough Skin
EVs: 252 Atk / 4 SpD / 252 Spe

  • Stealth Rock
  • Earthquake
  • Stone Edge
  • Swords Dance

(Side note, the only pokemon with Prankster T-wave/Will-O-Wisp are M. Banette, Sableye, Klefki, D. Gren, D. Amoongus, and Thundurus) No Elite 4 member uses a Prankster mon.