On September 28, 2020, Thomas Astruc revealed the full title of the special to be "Miraculous World: Shanghai: The Legend of Lady Dragon" in a comment to Le Figaro FR. He also stated that Marinette would reconnect with her Chinese roots in the special.
On May 29, 2019, Jeremy Zag revealed background concept art of Shanghai, although he didn't specifically reveal that the Shanghai concept art is for the upcoming promotional poster for this special. The caption of his post read: "New city. New Magical Object. New Hero. #zagheroez #ladydragon".
On July 31, 2020 Jeremy Zag posted on Instagram drawing of "Kwami cousins" named Renlings.
On June 15, 2020, Jeremy Zag revealed a new superhero, named Lady Dragon, who will appear in this special.
On October 5, 2020, Jeremy Zag posted on his Instagram a new image of the Renlings, but a few minutes later the post was removed. On October 8, Jeremy image posted again, but this time in color, with the caption "They are not Kwamis they are renlings, they can transform you into a wild animal you must control. Their owner is a very special person Ladybug and cat noir will meet in Shanghai! Coming very soon to you.".