Edited: “Oda directs the film” was misleading. He is the executive producer of the movie.
According to Weekly Shounen Jump published on May 11th, the executive producer of the new movie “One Piece Film Strong World” was announced to be the manga author Oda Eiichiro. Oda is also in charge of the scenario and the character designs. Production staff of an anime movie is usually organized independently of the manga author.
Key illustration of the movie
Oda said he would like to show the audiences a totally different film from the previous ones. He has discussed with all the staff involved and already drawn more than 120 illustrations for the character settings. The movie will be premiered on December 12th.
Source: Oricon