How to backup My Passport SSD with my another My passport HHD om MAC

Hi Community,

I’ve specially purchaised My Passport HHD 1 TB to backup data from My Passport SSD 1TB, but can’t get the point how to do this.

Forums and specialized WD resources saying that I should use TimeMachine (native Apple sofware for backups). But the case everywhere discussed - is how to backup data from Mac to My Passport using TimeMachine. Not the case of data backup from one My Passport to another.

In TimeMachine Options it looks like My Passport SSD should be included in the backup(and I can’t exclude it), but after backup process is done - it is not there. This is visible even loking on Estimated size of full backup comparing to the size of My Passport itself.
Monosnap 2020-01-14 10-40-07
The same can be done by using WD Backups on Windows…

Did anyone have any experience to backup data from My Passport to backup data from other My Passport