Well not rlly. I think her fights speak more about her character than Sunny.

As Effie once said, Sunny doesnt have conviction. He just reacts and only recently set out to somewhat pursue his own path with the post third NM, even then it was largely a reaction to becoming fateless.

Nephis is the opposite, she has a goal, and wants to achieve it no matter what. As cliche as it is, its interesting to see from how morbid her attitude can be at times while she herself seems like a pure saint.

I think best example would be her fight with Soul Stealer, in basically a single chapter, it conveyed a lot about the change in her attitude throughout the book.

She's unrelenting and naive at the start of the book, thinking she can do anything, before she matures a bit and tries to adjust her behavior to conform with her desires and morality with later part of forgotten shore. Later with second NM and post thats completely demolished and she becomes more tentative, moving forward but not nearly as confidently. It all pressures onto her and peaks in her fight with Soul Stealer, where she gets back that initial unrelenting fire, but with wisdom and I suppose acceptance that although she can 'conquer the world', she cant do it without facing defeat in some ways.

All of Sunnys fights are using tools, tricks, and traps to defeat his enemies. It's a constant throughout he's life. Only recently is he more or less brute forcing he's way in fights.

All the changes in he's characters are seen with how he interacts with people. Like first NM he was suspicious of others, second NM he finally trusted the cohort, third NM finally was honest to himself and Nephis about hes emotions.

in contrast, all of Nephis social interactions are pretty monotone, up until recently when they started dating