@Banhchuoi
Yes, I can see what you said but then again Britney is not "good" and still reacts to some things like it was in the novel she read, so calling Britney, the kid "white pig" is just how the readers of the novel called her so she kept the title since everything indicates that "fate" is forcing the MC in the same position as the Britney from the novel.
For the MC it doesn't matter they are children because they are her "destruction flags", if they are innocent or not doesn't matter. To show she is still just a normal person she even made friends with Follower2 because of how cute she is even though she knew that would lead to disaster in the future.
Another thing that I agree with you but also gave up on is the idea of the MC being an adult with memories of her past life in the body of a child, it is a cliched in isekai stories in general but it seens to be especially true in otome isekai that the author forgets that plot point and it is just there because but doesn't really matter as it doesn't change the character, when we get to know the character before the memories, or is quickly forgot to open space for the children character instead of having a child acting like a modern time adult.
Actually the only ones I see do that well are the "reincarnation of a powerfull being" ones, since the character is already a fictional adult from some time they keep the adult characteristics instead of forgetting about it. Examples of that would be "Marked for Failure, the World's Strongest Sage Reincarnates for a Do-Over!" and "The Mage Will Master Magic Efficiently In His Second Life". One that does it well with a female MC is "The Cute Little Granny Girl Hinata-chan" but it is not fantasy setting and it is another reincarnation.