Hunger Switch

Causes Morpeko to change its form each turn, alternating between Full Belly Mode and Hangry Mode

Full effect

The Pokémon changes its form, alternating between its Full Belly Mode and Hangry Mode after the end of every turn.

In game description

The Pokémon changes its form, alternating between its Full Belly Mode and Hangry Mode after the end of every turn.

Pokemon with Hunger Switch

Using Hunger Switch in Cobblemon

Abilities are passive and always active, so Hunger Switch costs you nothing to run. If it is marked hidden on a species above, expect it to be harder to obtain: servers differ in whether hidden abilities come from breeding, an Ability Patch, or events.

See the Pokedex for which abilities each species can have, and IVs, EVs and breeding for how to actually pass one down.