I'm predicting that Toriel won't get a weird route, it will be exclusive to Noelle.

I feel like people are forgetting that Noelle is set up as one of Deltarune's main characters, not just a supporting character like Berdly, but she's actively one of the 3 main Lightners, and Noelle has a specific association with "breaking" video games and finding secrets.

The Survey program points her out along with Susie and Kris as being significant when you input their names, Noelle's family: Dess, the Mayor, and Rudy, are all set up to be important plot points, Noelle is important to the backstory of hometown, Noelle is already a main character in Chapter 2, Queen sees Noelle as strong, Noelle is a playable character, she was sought after by Spamton and the man behind the tree, she found a strange hidden room in Dragon Blazers that nobody else could find, etc.

So I don't think that a Weird Route will just be something that anyone can do, like Toriel.

Toriel, while relevant to Kris, isn't a main character and isn't set up to be that important to the main plots of the Dark World or Hometown's mysteries. This is further implied by Toby saying Chapter 3 will be a less plot relevant Chapter, which makes it more likely that the characters significant to specifically Chapter 3 will be less plot relevanr to the overall story.

Noelle is also specifically mentally vulnerable to being manipulated by the player. Her life is in ruins, she thinks she's powerless, she has access to a strange spell, and she has a knack for breaking video games.

Regarding the Weird Route, I'd also not be surprised if Chapter 3 features very little consequences from it, as the characters there won't be involved with Snowgrave.