In Marvel comics, the character is a Russian spy who is first foes with Natasha Romanoff, although later they get on the same page. Originally introduced in 1999, Yelena Belova also has ties to Hydra, S.H.I.E.L.D. and Vanguard and has also held the title of Black Widow. Her inclusion in the prequel (if it is a prequel) would makes all the sense in the world if the crate label proves true.