Save notes in different places

I would like to keep a hierarchical structure of folders and files in my file manager while using joplin. More precisely, I would like to be able to save a note (in markdown) to one folder and another to another one in a completely different location. I do not work with a specific folder dedicated to notes. Notes could be in any folder.

I would like to tell joplin to always and automatically save this note to this folder and another note to another folder (without reproducing the hierarchy of joplin notebooks).

Is this possible yet?

"Save Note as MD" module exports all notes to the same folder: not what I want.

AFAIK : No.
As I understand your question the critical point is, that, you can export single notes anytime, but not automatically to a certain and from note to note different location.