Yes! I love Natasha/Maria in the MCU! I've written them a little but want to do more, because I think they're both really into control of various kinds, and having/losing control is so interesting to play with, for both of them. I imagine that they have a sort of fuckbuddies relationship, they've had sex a bunch of times, but neither of them really does traditional monogamy or romantic love. BUT honestly I would read pretty much any variation on that pairing.

PS, have you watched Avengers: Earth's Mightiest Heroes? It doesn't have much in the way of Maria/Natasha in particular, but it does have LOTS of great Maria action, and I love the way she's characterized in the show. Plus there's Janet and Carol. :D