Student drops and transfers in Moodle™ are not synced to WebAssign. Transfer students between sections in WebAssign before transferring them in Moodle.
If you transfer a student first in Moodle, you might not be able to transfer their work in WebAssign.
For advanced integrations, scores for transferred work might not automatically sync to Moodle. If not, the transferred student should re-open an assignment from Moodle to trigger the sync.