After the events of the previous year, the increase of population and the rise of the Flag Smashers, Sam Wilson and Bucky Barnes are both having a hard time adjusting to their new lives. Sam being looked upon to carry the 'Great Captain America' legacy and Bucky struggling with his own morals. When the world's safety is put at risk, the two team up again and see that the only way to bargain with the notorious Karli Morgenthau is to take the help from an old friend, recruiting her and her 𝗽𝗼𝗸𝗲𝗿 𝗳𝗮𝗰𝗲. Breaking her out of a maximum security prison she joins the heroes on their mission to save the world. But could this team up bring more than just peace? A newfound romance lurks in the air as the tension between her and Bucky grows. [Post Endgame] [TFATWS AU] [Bucky Barnes x fem!reader]