Headcanons for altertale! Your storyshift ones where really good and Iād love to know more with another underrated au
Sounds like fun, alright, here's a few:
From what I know, while the six characters who switched places do take one most of the personality of the character they switched places with, they do still retain some of their own. So I say that Sans and Papyrus remained in contact far more than UT Asgore and Toriel did. Papyrus' visits to the Ruins are tense, but not infrequent. And Sans always lets him in, even if he doesn't entirely approve of his methods.
Instead of the butterscotch cinnamon pie slice, Sans gives Frisk a little slip of paper woth a pun written on it when they go to sleep. Said piece of paper has the exact same effects as the slice of pie when eaten. It can also be gifted to Asgore during the fight with him to end the fight (he's too frustrated to continue) and to Papyrus to lower his attack/defense
During the date with Asgore, instead of wearing the sporty fit UT Papyrus wears, he's wearing a royal outfit. He insists that it is simply all the latest fashion, truthfully though, he just really admires the king for the way he manages to shoulder all his duties and yet never loses his smile.
Instead of chugging ketchup on the date with her, Toriel downs a whole bottle of hard liquor. Girlie is not playing around. Life is tough as it is, and having to deal with yet another human who is inevitably going to die on her watch is not something she's willing to deal with sober.
Instead of stripes, little white lab coats are what kids wear in the underground. Literally just because the idea of Gaster and Chara running around looking like little nerdy scientists is adorable. Frisk also happened to wear one when they fell
Papyrus is very conflicted during his fight. Again, they do retain some of their personalities, so I imagine that, instead of killing the human, the first few times he just knocks them out. If the human persists, he changes his strategy

















