Vision not being in the film was kinda strange to be honest but I do get why he wouldn’t be needed for her to have kids in other universes. It’s not explained very well, like a lot of things in this film. My take away is that Vision is basically a robot incapable of having kids, so obviously Wanda would’ve had to have had them some other way in these alternate universes. I presume our Wanda saw these kids in her dreams, not realising they were from other universes, so when she had them in Wandavision they ended up being those exact kids, right?
I kinda felt like they weren’t showing enough throughout the film, like they spoke about a lot of stuff that had happened but They could've just made the film longer and shown us.
Also I remember someone saying a while back that the reshoots were to tone Wanda down, that she was too brutal, too evil.