Warning! In screenshots are small spoilers for Chapter 2 in Northern Winds: Dragonships
I personally use CSIDE for ChoiceScript writing and Word for any other writing. CSIDE I think is the best tool there is for working with CS.
Here is example of that in my current project:
Then for worldbuilding part (places, chars, culture, mythology, notes etc) I use OneNote. It can be accessed from anywhere, be it on browser or on phone if you have MS account.
Example:
You can even draw there and use text-to-speach.
For tracking stat changes and choices I use simply Word. It make super easy to know how to scale difficulty for any skill check. And as with any OneDrive thing can save automatically to cloud. (I once lost txt file for stat tracking and was super frustrated!)
Example:
This is my work pipeline. Very likely not for everyone, but it works superb for me. Before this back in 2017 I used just notepad++ (As I use it for script writing at my day work) and changing into this style has made me to progress and plan story way faster.