We know that Margot Robbie, Jai Courtney, Viola Davis, and Joel Kinnerman will all be back reprising their roles from the first movie. Beyond that, it’s been reported that Idris Elba, David Dastmalchian, and Daniela Melchior are all on board. While these names are essentially confirmed, and some of them even have roles attached, most of them haven’t been confirmed through any official studio source.
Article source: https://www.cinemablend.com/news/2479585/james-gunn-updates-fans-and-shut-down-rumors-for-the-suicide-squad