For the above strings the English language sentences are:

"Allow users to add a repository instance into the course (can be configured only by admins)" and

"Allow users to add a repository instance into the user context (can be configured only by admins)"

If a filesystem repo can only be added by admins, we are not allowing users nor teachers to add repository filesystem instance. Thus, if admins need to configure user and course filesystem repos anyway, a rewording could be:

"Enable user repository instance (can be configured only by admins)"
"Enable course repository instance (can be configured only by admins)"