Vikavolt @ Buginium Z  
Ability: Levitate  
EVs: 160 HP / 252 SpA / 96 SpD  
Modest Nature  
IVs: 0 Atk  
- Protect  
- Endure  
- Bug Buzz  
- Substitute  

Zeraora @ Fightinium Z  
Ability: Volt Absorb  
EVs: 64 HP / 252 SpA / 192 Spe  
Timid Nature  
- Fake Out  
- Focus Blast  
- Calm Mind  
- Laser Focus  

Rotom-Wash @ Waterium Z  
Ability: Levitate  
EVs: 248 HP / 252 SpA / 8 SpD  
Modest Nature  
IVs: 0 Atk  
- Will-O-Wisp  
- Hydro Pump  
- Pain Split  
- Charge Beam  

What they do:

Vikavolt is an extremely slept on pokemon. It beats Electivire, Rotom-Mow, Zeraora, Heliolisk, and 50/50s Stunfisk as well as any FEAR you encounter.

Zeraora beats Manectric-Mega, rotom forms, Magnezone, and Heliolisk and 50/50s Golem-Alola

Rotom-Wash is able to 100% both Stunfisk and Golem-Alola

Team Weaknesses:
Vikavolt