A report from Badass Digest says that [Aquaman](movie:264237), The Flash, Cyborg, Lex Luthor, and Doomsday will all be introduced in the film – obviously, nobody knew about Doomsday, especially since the actor which was supposed to portray him was cast as Aquaman (Jason Momoa). Moreover, the same report says that Lex Luthor is the puppeteer, with his masterplan beginning to be developed during Batman v Superman: Dawn of Justice.
Reportedly (who may be seen in The [Suicide Squad](movie:2283363) also) hired spy KGBeast and other spies in order to gather information about all the metahumans in the world. If Superman is just a new addition, it isn’t the same with Wonder Woman – Lex Luthor knows about her, because he has seen pictures of her, pictures shot in the late 19th century.
This also comes to support another rumor, which says that the first [Wonder Woman](movie:45787) film will be set in the late 1920′s.
Source: Comic Book Movie