Yes it would make sense for Natasha to have crossed paths with Killmonger especially if he is an American black operative that apparently was a War Dog. Killmonger apparently worked for the CIA especially since Everett Ross knew who Killmonger was referring to him as "one of ours". Killmonger apparently was in Afghanistan, Iraq and so many other places raking up kills so it would make sense that he and Romanoff might have crossed paths.
Natasha crossing paths with Bucky too makes sense especially for her film if it ties in with Captain America: Winter Soldier (2014). Natasha even said as much that she and Bucky crossed paths. Hell she knew so much about him but also about his connection to Steve.
It would only make sense for Sebastian Stan (Bucky) to be in her film but how about Samuel L. Jackson (Nick Fury)? Fury should definitely be in her film especially if it is a prequel and that would mean Coulson he would have to be in her film especially if her film ties in with SHIELD/HYDRA.
Natasha crossing paths with Bucky too makes sense especially for her film if it ties in with Captain America: Winter Soldier (2014). Natasha even said as much that she and Bucky crossed paths. Hell she knew so much about him but also about his connection to Steve.
It would only make sense for Sebastian Stan (Bucky) to be in her film but how about Samuel L. Jackson (Nick Fury)? Fury should definitely be in her film especially if it is a prequel and that would mean Coulson he would have to be in her film especially if her film ties in with SHIELD/HYDRA.