You can SEND them to a
device using the Template Language
but
https://manual.calibre-ebook.com/faq...lder-structure
You have 2 choices for the Library:
1) Use Calibre with all its features and abilities (and its filing system)
2) Don't
Option 1 means you don't even need to know HOW it is filed (as long as it is on a local drive). The UI is a
super card catalog and a
gofer (go for and get me this book
)