
I think it's more about her psychology and how the child-ness is intermingling with the adult-ness in a confusing way for her. When she first showed up in that body she was confused and scared. Later when she realized she was part of the story, she didn't realize what her purpose or her "role" was and that made her upset because "why was she even put there if that was the case".
I guess you can think of it as the internal struggle that she as a main character is constantly thinking about. Also, she does occasionally use or thinks about the original plot.

she already mentioned that what she knows about the story won’t be helpful yet as the story she read started when the prince will reach a certain age (i forgot) but something like that. i like it better tho coz the story is not gonna be focused solely on her as a transmigrator and she can do whatever and act however she wants but at the same time she can also have the advantage of knowing a bit of the future (sorry if my english was bad. not my first language)

She does use it but not really to the point that it heavily affected the plot and with the psych, they could’ve made it about her mental struggles of being an adopted child or abt being more mature than her peers, it could’ve been anything at all and the story (as the novel did) would’ve still be the almost the same
Why do I feel like Leo being a transmigrator is kinda irrelevant to the story? It’s season 2 and other than the fact that she’s more mature and smart for her age, her knowledge of the story isn’t really being use?? And from the spoilers, it doesn’t seem like she changed the ogstory that much. They honestly could’ve just made her a really smart and mature child but ig making her a transmigrator would attract a larger audience since transmigration stories has it’s own fandom.