Overcoat Pokémon can pose unique challenges in battle due to their ability to nullify weather effects like rain and sun. To overcome this, consider using Pokémon with abilities like Drought or Drizzle to manipulate the weather, giving you an advantage.

Additionally, utilizing Pokémon with moves like Solar Beam or Hydro Pump can directly target Overcoat Pokémon, bypassing their weather immunity. Alternatively, status moves like Toxic or Will-O-Wisp can also be effective in weakening Overcoat Pokémon over time, gradually depleting their HP and making them more vulnerable.