Unnamed island (PK04)

An unnamed island in the Orange Archipelago appears in Pikachu's Rescue Adventure. Its location is unknown, though assuming the events of the short take place following Bound for Trouble (the short, along with The Power of One, hit theaters two days after the episode aired), it is quite likely one of the two tiny islands to the northeast of Fairchild Island.

It is unknown if this island has a permanent population; however, there is a located there.

Pokémon seen on the island
Isola senza nome (PK04) 无名岛（PK04）