To put it simply, after a true reset chara still remembers everything. But the narrator doesn’t

The best example is the water sausage where the narrator has no clue what they are, but chara would after a true reset. The narrator is still surprised by the twists and turns of the story despite remembering everything.

This doesn’t make since if chara is the narrator. Most likely it’s just a normal ass quirky rpg narrator like what was in earthbound

The ghost argument doesn’t help either. Multiple times says things to the degree of “turn mettaton around” yet mettaton does not hear. Otherwise mettaton would instantly know what frisk is trying to do.