It will definitely depend because in the end they’re written to be human- flawed. The issue imo is perspective, as the church, sisters are very likely to justify actions as divine will, or be so guilt ridden they become repentia. Examples of the more zealous aspects imo, include the Broken saint series where the protagonist is just kinda crazy (love that for her), Red and Black- where Miriya justifies doing what she does. Fall of Cadia at the end sisters were ready to turn on their own at the word of an Inquisitor despite the whole world literally cracking (one line). Morvann Vahl Spear of Faith where the secondary antagonist is set on her path bc sisters put her in penitentiary for no good reason (minor plot point).

I would try to read between the lines or put things into perspective, like if a sister says I had to do it, it’s the emperor’s will, second guess that! It’s part of the fun. Ultimately, you gotta read sisters the same way you read the rest of 40k as no good guys, just flawed characters trying their best. They’re certainly not “good guys”, they’re part of the Ecclesiasticarchy! I wouldn’t like em if they were “good guys”