Fans are learning through snippets of new footage how Wanda's powers work and affect reality around her. This includes turning a standardized Hazmat suit into a beekeeper suit, which caused Wanda such an adverse reaction to seeing that she, literally, rewound time before Wanda and Vision saw him exiting the maintenance hole cover.
Co-executive producer Mary Livanos teased that Monica being involved in WandaVision would itself be a mystery about “how the heck would she become involved in this odd sitcom that Wanda and Vision find themselves in.” As shown in the first two episodes and countless trailers and teasers, Monica herself seems just as confused as fans.
In the first featurette for WandaVision about the story, never-before-seen footage was shown, including Randall Park's Jimmy Woo and Teyonah Parris's Monica Rambeau inspecting something odd at the border of Westview.
Monica is seen reaching out and touching some kind of barrier that causes her hand to become static and even lose its color, which matches the era in the first two episodes.
WHAT THIS MEANS
It seems apparent that S.W.O.R.D. must enter the bubble surrounding Westview wearing hazmat suits to prevent from being affected by the sitcom realm altering their minds. Monica Rambeau could have unwittingly passed through the barrier without any protection.
What seems to have happened, as many fans have already theorized, is that Monica entered the barrier in the 60s era and is clearly confused about her surroundings until she shakes Wanda's hand and has a name for herself and her own “character.” Then in the 70s, Monica has a much more prominent necklace showing off the logo for S.W.O.R.D., which Wanda is familiar seeing on the oddly colored toy helicopter and ominous beekeeper.
Upon seeing it, Wanda instantly distrusts Monica, asks who she is, only for Rambeau to say “I don't know” in a panic, before presumably being blasted out of Wanda's world as an intruder, which fans saw in the first trailer. Interestingly, Monica wasn't returned to normal upon exiting the warped reality, still wearing her 70s attire. It will be interesting if this implies that Wanda will be able to alter reality outside this limited area she's essentially claimed.