How did Wanda know about nexus events?

Question

In the seventh episode of WandaVision, Breaking the Fourth Wall, the advertisement states:

Feeling depressed? Like the world goes on without you? Do you just want to be left alone? Ask your doctor about Nexus. A unique anti-depressant that works to anchor you back to your reality. Or the reality of your choice. Side effects include feeling your feelings, confronting your truth, seizing your destiny, and possibly, more depression. You should not take Nexus unless your doctor has cleared you to move on with your life. Nexus, because the world doesn't revolve around you. Or does it?

The advertisements are

controlled by Wanda, as is the rest of the hex.

This is obviously a reference to nexus events, which are explained in Loki. However, to create this, Wanda would have had to know about nexus events. There hadn't been anything to suggest this, nor are they common knowledge (in fact, it is impossible to know about them if only one timeline exists).

How did she know about nexus events?

Answer 1

I don't think Wanda knows about Nexus Events - and I don't think she was responsible for that specific advert.

Throughout Episodes 6 and 7, Wanda's control over the Hex is slipping and Agatha's is increasing, as demonstrated on several occasions:

• The arrival of Pietro at the end of Episode 5 was Agatha's doing, leaving Wanda confused about how it could have happened without her knowing
• The theme tune for Episode 6 makes several references to how things are spiralling out of control and descending into chaos
• The ad seen in Episode 6, for Yo-Magic yoghurt, basically spells out Agatha's entire plan: to drain Wanda of her magic and leave her a withered husk. Again, this is something that Wanda cannot possibly have known about, therefore Agatha must have been responsible for that ad, not Wanda.
• At another point in Episode 7, during one of the mockumentary scenes, the camera operator (later revealed to have been Agatha) asks Wanda "Do you think maybe you deserve this?", which shocks Wanda, as the camera operator shouldn't be able to talk.

So my belief is that Agatha was responsible for that particular advert, not Wanda. Of course, how Agatha knows about Nexus Events is a very good question, though it's clear that she has a much better grasp of the supernatural than Wanda.