Flower Gift

Increases friendly Pokémon's Attack and Special Defense to 1.5× during strong sunlight.

Full effect

Friendly Pokémon have 1.5× their Attack and Special Defense during strong sunlight if any friendly Pokémon has this ability. Unlike Forecast, Multitype, and Zen Mode, this ability is not tied to its Pokémon's form change; Cherrim will switch between its forms even if it loses this ability. As such, this ability also works if obtained by a Pokémon other than Cherrim.

In game description

Boosts the Attack and Sp. Def stats of itself and allies in harsh sunlight.

Pokemon with Flower Gift

Using Flower Gift in Cobblemon

Abilities are passive and always active, so Flower Gift 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.