In Merchandise-Driven media it's typically pretty easy to set apart the characters whose toys are getting advertised. They're the ones that take the spotlight in any given story, save the day in the end, etc., or are otherwise just made to look cool by the narrative itself. They'll have more character development, more detail in their character model, more gadgets; everything about them screams toyetic in loud plastic-mould colors. If a major female character from a Merchandise-Driven series ends up as a Toyless Toyline Character, it's probably because of The Smurfette Principle.