I sort of thought that the end credits scene could be a teaser for the plot of Captain America 4 instead of Hawkeye but maybe I'm way off base, they just seem like natural supporting characters for that film and julia louis-dreyfus being in that and in TFATWS
But she literally showed Yelena a picture of Hawkeye.
Like at best it could be ambiguous and tie into both Hawkeye and a future movie, but it definitely still ties into Hawkeye.