Instead of selecting only one class at a time to copy to via Direct Share, select multiple classes at once just as when importing from Commons. Even better, allow for teachers to select posting to multiple other classes right at the beginning during the creation of content and at editing.
Why make teachers select a single class to copy to, click copy and then have to repeat that 6 or 7 more times to copy the same assignment for the rest of the classes they need the assignment in? And while you are at it, why not set the creation of an original assignment, page, quiz, etc so that teachers can already select multiple other classes where to post it to just like EDSBY? That's is actually one of the main features why many teachers prefer EDSBY which is more intuitive and you can post easily and fast into the multiple classes you select right there during the original creation or editing.
Hopefully it doesn't take Canvas years to include the option to post pages, assignments, quizzes and modules to multiple classes right from its creation instead of all this frustrating workaround of having to unnecessarily click hundreds of extra times per day to accomplish such a simple task.
They will tell you to create content somewhere else like in the Sandbox. Then find it listed, click on the right side dots, then click copy to, then select the single class you want to copy to, click to copy and then repeat for each of the rest of your classes. Or create it in the Sandbox, exported to commons, go to commons, click to import it back, select all the classes you want to import it to, but lose your due dates, so then you have to go into each class and edit each one of the dates of the item. I say, skip all that and simply include the option to select posting to multiple classes right from the beginning.