The finished film behind the working description
Marvel's official film record identifies Captain America: Brave New World as the story of Sam Wilson after taking up the Captain America mantle. Anthony Mackie plays Wilson, with Julius Onah directing. The U.S. release date is February 14, 2025. A development headline calling the project Captain America 4 therefore points to this film, rather than to a separate movie still awaiting a title.
The cast includes Danny Ramirez and Harrison Ford, with Ford portraying President Thaddeus Ross in the film's premise. The central setup places Wilson in an international incident after meeting the newly elected president.
Source [1]A mantle and a character are different
Captain America is the heroic identity Sam Wilson has assumed; it does not mean Mackie is playing Steve Rogers. That distinction helps when following a franchise across several actors and characters. Marvel's cast and synopsis provide firmer evidence than an old numbered working title. For Mackie's different role in a supernatural comedy, see the related We Have a Ghost introduction.
Source [1]