You can upgrade from VSR 16 to VSR 18, yes.
For the additional copy you can use the offsite copy feature.
When you create a flash drive that contains the VSR recovery disk, you can boot that drive and run a bare metal recovery.
On the off site copy feature, is that another copy of the image file or a file by copy of the original data?
As far as the bare restore, I know how it should work. My question relates to the many issues we had making bare metal boot discs/drives with Veritas 16 in 64 bit Windows 10. Perhaps those issues have passed.