This who I consider best represents each character or vis versa.
Frisk = Six
Chara = Dark Six
Flowey = Nome
Toriel = The Granny
Sans = Twin Chef #1
Papyrus = Twin Chef #2
Undyne = The Farryman
Napstablook = The Wax Bellman
Aphyse = The Janitor
Mettaton = The Hanging man
Asgore = The Lady Gashia
Asriel = Seven/The Runway Kid