I do iCloud backups but I also like to have full copies on my computer. They are eating up close to half of my 1TB SSD. Is it possible to save or move them to an external drive?
It could be as simple as dragging and dropping files, but I cannot remember how backups are saved in iTunes.
But, there are other things that would work, but might not be as convenient as dragging and dropping.
Maybe changing the library to the external drive would work.
One thing that I know would work without a doubt, but might be inconvenient for you is installing an OS on an external drive and use it for backing up your iOS devices.
This would definitely work, but there could be simpler methods to try first.
Backups are saved in ~/Library/Application Support/MobileSync/Backup/, just copy the folder in Backups with 40 random chars in name to an external drive.
But imo better get iMazing, it can set backup location to an external drive. Also, it can store multiple backups, and won't eat much space as backups are incremental. On sale here for $20.
I wrote the above because last time I tried it it was necessary to disable SIP, but not sure that is true in latest version. Try without disabling SIP first.