I did read man page before I post my question here, I couldn't figure out. mv -v doesn't help, I want to see the progress (like percentage of transfer)!
If this helps anybody in 2022 - you can check the progress of mv without installing any additional programs by opening Activity Monitor and going to the Disk tab. Look for the process name 'mv' and then check bytes written, it will show you how far through the transfer is. eg. if you are moving a 20gb file with mv and bytes written is 10gb you know the progress is 50%.
not an exact solution as part of the mv command but it gave me the piece of mind i was looking for when transferring files 🙂