Hi.
Some years ago (2005), someone raised the following question [1]: "want to backup this whole category with courses. is it possible? and how do i?" This question is opened since this year. The last post under this discussion topic was in 2012. Here it is: "Is there already any solution for this?"
Well, I'm here to post a possible solution to this issue: BrCLI (Backup & Restore Command-Line Interface) [2]. It is a command-line plug-in integrated in Moodle that allows administrators to performs bulk backup and restores of all categories, not just a single course.
I hope you enjoy.
Best regards. Paulo.
References:
[1] Available at: https://moodle.org/mod/forum/discuss.php?d=19351
[2] https://moodle.org/plugins/tool_brcli