Yes you can do it vise versa as well.
When you sync from the Desktop >> create a collection >> Add Images to it >> Sync
From Mobile, you need to add images from the Gallery to Lightroom Mobile app >> do the edits >> and it will automatically Sync from Mobile to Desktop Lightroom.
And, just to clarify, you need Lightroom CC. You cannot use the standalone version to synchronize from the computer to the phone.
Yes, I missed that.