I’d imagine it’ll cover her transformation from Spy and Assassin to Agent of Shield. Likely Hawkeye will be there and maybe Fury too in some capacity. Perhaps even a de-aged Robert Redford too. And, I’d guess, have a trip to Budapest.Plenty of SW fans and critics alike felt that Solo was pointless, and far from a "good story". Even so, Han is a hugely popular and important character in that universe. And though he ultimately dies (at the actor's insistence), he had already played a huge role in that saga. Does Widow carry the same clout in the MCU?
Edit: Furthermore, all previous movies in the MCU have had some context or importance to future movies. This will have none and be very much a stand alone project in that regard. Personally, I just don't have the desire for it.