I worked in university and had a case where a student did this, the grades didnt transfer as a result, and she failed as a result. If you’re gonna do this, make sure it’ll actually work.
If I remember correctly, the instructor synced the grades from that platform at the end of the semester, and because the student was “inactive” nothing transferred, so Blackboard gave 0s for everything. It was a mess. She appealed but it didn’t pass.