According to a report of Variety, right after the fact that Will Smith decided to officially dropped out of Suicide Squad 2, Idris Elba - who acted as Luther in The Office as well as Heimdall in the Marvel Cinematic Universe, were asked to join the film and play as Deadshot.

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Idris Elba

As mentioned above, Smith had no other choice rather than dropping out of Suicide Squad 2 as he had some scheduling issues. In any case, he had never actually confirmed that he'd be part of Suicide Squad 2 from the beginning.

Variety reported that Warner Bros - the studio which produced Suicide Squad - "moved fast" in order to figure out who could be the "proven A-lister" to substitute Will Smith. Eventually, it was Elba who got the call. However, there is no information about whether other actors have also been considered for this character or not.

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Deadshot by Will Smith

Also, we have not heard about any official announcements about casting for the next sequel of Suicide Squad at all. This also means that we still cannot guarantee who else among the previous cast would continue playing in this movie or not. However, Variety reported that there is a high chance Margot Robbie will return and play the role of Harley Quinn in the new film. The Joker was performed by Jared Leto in the first Suicide Squad movie published in 2016; however, it’s still unclear about his involvement in the sequel.

Joker And Harley Quinn Movie Script Details
The Joker and Harley Quinn as they appeared in Suicide Squad, portrayed by Jared Leto and Margot Robbie

From what Justin Kroll - a writer of Variety - reported, Warner Brothers also thought of replacing Deadshot completely instead of just recasting him.
While most aspects of the movie remain unclear up to now, Warner Brothers has brought a great news for the fans: the movie will be officially released on August 6, 2021. James Gunn - the brilliant director of Guardians of the Galaxy is said to be the one who will write as well as direct the movie.