WandaVision is three weeks after the return Snap. Falcon is six months after. But Falcon was planned to be aired first, and I am sure the scripts and everything but the filming that was delayed by covid was done, so I doubt anyone from WandaVison will appear. White Vision is probably not planned to appear again until the movies, as I don't think I ever heard anything about crossovers between the Disney+ shows. Netflix had their shows meet up in The Defenders, and Lucasfilm has said in advance that Ahsoka, Mandalorian, and the Rangers show would cross over into some big finale of their stories., but those were both announced in advance. I would have to dig up the Feige quote, but he did say crossover between Disney+ shows and movies is for sure.