Here is an overview of the content, via Bandai Namco:
In the latest downloadable content for One Piece: World Seeker, available as part of the Season Pass or to purchase individually, players will take control of Trafalgar Law, as well as introducing a brand new character to the One Piece world—Roule.
On the way to Skypiea to look for some Dyna Stones, Trafalgar Law picks up an “unfinished map” that accurately depicts the geography of the island. This map in fact belongs to a boy named Roule, given to him by his Dad who passed away during the war. Together, they decide to head to Skypiea – with their journey taking them directly to the Sky prison itself.
View the screenshots at the gallery.