This can be done, but you need some extra steps. TEST THIS ON A SMALL SAMPLE FIRST. The steps described here will not destroy data, but they can make a mess of your courses if you are not careful.
If you have a single activity that you want to import into many courses, first, create a course that contains only that activity. This is your template course.
You can then use the functionality in the "Bulk course upload" feature:https://docs.moodle.org/32/en/Adding_a_new_course#Course_templatesYou will need to create the file "uploadcourse.csv" as described in the documentation. Include ONLY the parameters "shortname" and "templatecourse". "shortname" indicates the short name of the course you want to bring the activity into. "templatecourse" indicates the short name of the course you are bringing the activity from (i.e. your template course with just the one activity in it).
For "Upload mode," choose "only update existing courses"
For "Update mode" choose "update with CSV data only"
Leave the other options set to "No"
Again, please be careful with this process and test carefully on a small set of courses before using it on a large number of courses. There is no automated way to undo the results of this process.