Finished B&W yesterday and it was outstanding.
Witcher 3 and the two Add-ons are among the Best Games i have ever played concerning Quest-/Worlddesing and Staging. Really Outstanding.

But - is there any Ending to B&W where Anna-Henrietta does not die?
When speaking to her and Syanna i tried different DIalogueoptions, but this always led to Syanna killing Anna-Henrietta.
Just courious if this is avoidbale.

Yes, it's avoidable. You have to empathise with Syanna, and what she has gone through her whole life. Don't be judgemental, and probe deeply into her story; listen to everything she has to say. Don't be a jerk, don't judge... listen! Then, in the final talk, an option to ask her if it's not worth reconciling with her sister becomes available. If you have been the listening ear that she desperately needs, you will get the good ending.

Also Anna-Henrietta survive if Syanna is killed by Dettlaff, in order to get this ending you need to choose to rescue Syanna from her prison rather than search for the unseen elder vampire. When you in the fairy tale world, DON'T get Syanna magic ribbon from the little flint girl.

It's so cool that kids cannot blindly figure it out by selecting "the right dialogue lines" highly immersive and a great game.