Symbiosis is an ability introduced in generation 6.
4 Pokémon can have this ability, such as Flabebe, Floette, Florges and Oranguru. For 4 of them it is the hidden ability, usually obtained from events, raids or breeding.
Official effect
Passes the bearer's held item to an ally when the ally uses up its item.
Flabebe
Floette
Florges
Oranguru