This would've been a whole lot better if the author didn't make her so stupidly naive while having literally two thirds of her thoughts being some random stupid villainess fiction plot.
It is a perception bias used almost identically like in I'm Really Not the Evil God's Lackey is doing. MC perception of the events is extremely different from how they are seen by others. The point is the gap of gravity between her trivial assumptions and how absurd the perspective of others is.
I am not sure if you have noticed, but sometimes even the dialogue differs between the MC perspective and other people she interacts with.
It could be that the entity that gave Evangeline the second life trough an inheritor's soul is silently guiding her and even filtering out things from her perspective to a degree, while keeping her in a relatively light atmosphere and romfan vibes.
The more I read about this the more it feels like the entity is using the MC as a software to adapt to human mannerisms more and our MC's "soul" is not even aware that this is it's purpose. Imagine if MC's soul only thinks that it's in control and she was actually always in the hindsight and was given only the immersive suggestion that she is "living" as Evangeline.
That would explain the slight differences in how the conversations went through depending on the perspective of who is reminiscing of the event. What we see troughs the eyes of the others is the entity. Wheat we see through the perspective of "Evangeline" is filtered rendition of what entity lets the reincarnated soul to experience and think that it is experiencing it directly, just to get the feedback of a human response from it.
Imagine such madness, where you are not really you, but just a tool for some sinister entity to learn how to become a human trough playing with your mind and with what it makes you think you are experiencing. You can never be free, as you are just an adopted mental construct and a concept in THEIR mind.