So we all know that the helicopter and the blood on Dottie's hand are just about the only things in color before the whole mass-colorization at the end of the episode. We also can fairly easily observe that there's that sort of "thud" sound when something foreign to Wanda's reality enters into it (and, I expect, when they leave), like the helicopter and the beekeeper.

I suspect that the helicopter retaining its color and being from outside the reality are intrinsically linked. If it was in color, it's not from the "WandaVerse" as it were. You could argue the beekeeper isn't in color, but my counter-guess would simply be SWORD intentionally sending them in a monochrome suit to avoid suspicion. The blood on Dottie's hand is technically native to the WandaVerse, but I would hazard a guess that while it's technically from the WandaVerse, it's not something that's supposed to be there. Nothing in your standard-fare sitcom happens often enough, especially not in the 50s-60s, where anyone would visibly bleed. Dottie still bleeds red because she's not supposed to even be able to bleed. And when she does, it registers as an anomaly.

We already know Teyonah Parris is playing Monica Rambeau, somebody Wanda (probably) hasn't met organically at this point outside the WandaVerse, so why, then, is she in black and white too instead of full color? My current theory is that she (and possibly other SWORD agents) were sent into the WandaVerse and got stuck, and were sortof "absorbed" into the fantasy, being written into the reality's status quo and being decolorized to preserve the norms of the reality. This then gets slightly more interesting when you realize that if Monica-Geraldine can be absorbed into the WandaVerse and get stuck, it could very well mean that any other number of people in the show that we've met so far could also be trapped SWORD agents. In other words, Wanda could be inadvertently holding these people hostage. "Who's doing this to you?" could easily be a question of "why are you keeping these agents in there?" given that her track record as an Avenger would run counter to anything that would suggest that she would willingly be trapping people in an alternate reality. Resolving the plot of the series could go from being a rescue to get Wanda out of the clutches of somebody like Mephisto to being a mission to get a not-insignificant number of SWORD agents or other bystanders out as well.

Does this hold any water? Am I making any sense? Let me know. I'm super excited to see what comes next and may even come back to adjust this theory as new episodes come out. Thanks for the read. :)