Let It Rain, Let It Pour Pokemon Legends Z-A Side Mission Full Walkthrough and Guide

Unlocked after the strategy meeting during Main Mission 20.

The trainer is waiting for rain because their Pokémon are stronger when it's raining.

[1] Talk to the lady. She talks about weather during Pokémon battles and how it could affect the fight.

[2] Battle her and win.
・Here is her profile.

Note: She gives you the tip that Water Type moves are stronger in the rain, while Fire Type moves are weaker.

・₽2,000
・Mystic Water x 1
・Fresh Water x 3