If there's word from the devs themselves saying that the character is meant to be interpreted as evil as
@WolframL has pointed out, then it's pretty straightforward to me that she's meant to be evil and any content written that relates to her in the main story by the devs will intend to get that across.
I do however understand why people see ambiguity if not for the express word of the devs, and I am not someone who plays a masculine, "pitching", character. I'd remind you
@Alypia that until very recently, premarital sex, and a whole slew of other things this game takes for granted were considered evil or in some way untoward, backwards, dubious or morally suspect. In fact, they still are considered evil by many people in spaces outside of this forum. Guys taking dick? Femboys? Unwed mothers? Demons and pacts with pagan gods? A woman having sole autonomy over what is done with her children? This entire game is evil.
Also not too long ago, within the last 100 years even, many women essentially had to make the trade of "I will bear children for you and take care of the home in exchange for not being disowned or looked down on by society" since there's legally a hell of a lot they couldn't do without being attached to a man, and the entire history of aristocracy IRL is basically baby trading for power.
Humor me for a moment. Pretend that you rewind the clock to the period of time that inspired the game. Remove all meta game context that we know like the dev's intention and Evergreen is real. Is she evil? Or is she taking the role of the male lord over a piece of land with the expectation that your player character is "the woman" with regards to decision making about children? What is the substantive difference between the two other than the soul transfer bits? I think its more interesting that the thought process we have is "obviously, she would be evil".
Throwing around the word evil in this game in full societal context is not the entirely obvious thing some people seem to think it is - especially when the game itself relies on aesthetics and power structures in the referenced parts of "medieval fantasy" history.
Evergreen is evil for babymaking with the intention of transfering her soul to new vessels. Sure. And I guarantee that Carmen the Baroness has a recent family history of marrying of young women in her family to much older men for alliances and control over land - and I'm certain that someone else she knows is married to and happily banging their first cousin.
Edit: I edited a typo "holder to older" as of the 26th, and I can see how the language here of "Guarantee" and certainty would lead someone to believe I'm literally only commenting on Carmen. I have not changed that language to hide it as of this edit, its a fair misuse of language to point out. Just the mentioned typo.