Is Kaguya from Naruto Good or Evil?

She's plainly evil.  But like many villains she doesn't start that way nor perceive herself that way.  She starts good, and it's her involvement in the human world that traumatizes her and makes her come to believe humans are inevitably harmful to nature and each other.  Her trauma leads her down a dark path where her goals are clearly things that are evil when viewed from a third party, but to her, she's merely fixing a problem.  She's the hero from her perspective.

Somewhere in between.  Kaguya was originally a good person and still has traits of that. She cared a lot about the planet and overall wanted peace. But her lack of faith in people and gaining absolute power eventually corrupted her. She began using her power to forcefully bring about that peace and extinguish any who threatened it or her.

So she wasn't a sadistically evil person and has motives of protecting the natural world as a whole, but her character was marred by darker traits that twisted her into someone cold and ruthless when it came to humans, who were the problem in her eyes.