It’s been a year and a half since the Avengers split, and Natasha has been hiding out as a fugitive somewhere in the world. Out in public one night, she sees you, someone she never thought she’d see again.

This is set around 6 months before Avengers: Infinity War (December 2017), and I believe a few months after Black Widow, the location can be of your choice, and it's implied that you're an Avenger, but you could be anyone that she knows.