Titled Infinity War: Prelude #1, the comic shows an extended version of the end of Captain America: Civil War in which Black Panther officially apologizes for falsely accusing Bucky of killing his father.
This evidence specifically comes courtesy of a brand new Marvel comic that’s going to tie together some of the backstory leading up to Avengers: Infinity War.
After that reconciliation, he makes a promise to help The Winter Soldier, and we see more scenes of T’Challa’s sister Shuri sifting through Bucky’s bad memories and his Black Order stroll into town.