10 Worst Things Black Widow Has Ever Done
9. Trying To Kill Captain America - Secret Empire #7
While Black Widow is definitely a hero for the course of Secret Empire, it is also worth remembering she doesn't have an entirely perfect run from a moral perspective, as she does try and straight-up murder Captain America within it.
Now, in any other circumstance killing Cap would be the worst thing ever - but he is a huge Nazi supervillain in Secret Empire, and Nat is mostly trying to kill him so that the vision of Miles Morales killing him doesn't take place, as she doesn't want the cheerful young Spider-Man to become a killer so early in his life.
However, it's also worth mentioning that kidnapping Steve would have been as useful, and also would have given the team time to find a way to turn Captain America back to normal, instead of just murdering him because he'd gotten brainwashed by the Cosmic Cube.
In short, it's the wrong thing done for the right reasons, leaving it one of the sketchier plans Black Widow has ever tried to execute.