I used to do that until Moodle release 3.2.
As a course manager, I could restrict some sections to a teacher and some other sections to another teacher, using groups. Just changed capabiilty moodle/course: viewhiddensections to 'deny'. The section restricted to the other group used to become hidden to the editing teacher.
Now, after release 3.3, this is not working anymore. Even with that capability set to 'deny', all teachers became able to see all sections.
Do you have any idea of how that could be achieved now?
Thanks in advance!