Nah I think A4 starts off immediately after the effects of this, probably the first 30 minutes or so is Danvers answering the call, the fallen Avengers picking themselves up, Tony finding a way to get back to Earth, eventually I think Scott is the glue that brings them together (Danvers + the rest) then we probably get a time jump like 4 years later and that’s when we get the older Tony probably working with Shuri and Pym figure out a way to travel through realms and somehow gathering alternate versions of the lost Avengers to fight Thanos one more time...I don’t know how else they could pull it off..