Gen 9 NU Dual Screens

Klefki @ Eject Button
Ability: Prankster
Tera Type: Ghost
EVs: 252 HP / 64 Def / 192 SpD
Bold Nature
IVs: 0 Atk
- Light Screen
- Reflect
- Spikes
- Steel Beam
Despite RU banning Light Clay and Alolan Nintetales existing in NU, Klefki is still able to pull off a dual screens set for HO teams in NU. This is thanks to its Ability Prankster as well as the item Eject Button. Prankster allowing it to move first most of the time to get off a screen or both is what allows Klefki to pull off a screens setting set with Eject Button. Alolan Ninetales can't really use Eject Button with Aurora Veil since faster Pokemon such as Kilowattrel, Inteleon, Scream Tail, and Choice Scarf Pokemon such as Munkidori, Flamigo, and Flygon exist.
How this set works is pretty simple. You typically lead off with Klefki and use Light Screen and/or Reflect depending on the Pokemon in front of Klefki. With Eject Button, Klefki can switch out after being hit by an attack after getting off one or both screens to safely bring in a setup sweeper such as Drednaw and Bulky Double Dance Porygon-Z. Spikes allows Klefki to setup a hazard to chip grounded Pokemon that aren't wearing Heavy-Duty Boots. Steel Beam is used for the STAB move on this set to potentially have another way to bring in a setup sweeper after Klefki sets up screens should Klefki be at 50% HP or less. Tera Ghost is used to block Rapid Spin and become immune to Fighting moves should you need to Tera Klefki.
The mixed EV spread prevents Download Porygon-Z from getting a Special Attack boost when it is out against Klefki. You could use a max max EV spread of 252 HP / 252 Def / 4 SpD or 252 HP / 4 Def / 252 SpD with Bold / Calm Nature instead. This set is only used on HO teams, so this set is seen with setup sweepers such as Bulky Dual Dance Sitrus Berry Porygon-Z, Drednaw, Shift Gear Toxtricity, Booster Energy: Speed Scream Tail, and Flygon.