TL;DR
Sure.
Set up a brand new OS on a clear partition on a secondary drive (i.e. the exterior SSD), then copy the purposes from the previous Purposes folder to the Purposes folder on the brand new set up.
Drag and drop set up
Most purposes (if not all) that are put in by merely dragging and dropping may be copied to any folder (be that on one other, exterior disk or the interior disk) and run from there – test it your self.
Seeing as exterior arduous disks are handled as directories, by the OS, as soon as they’re mounted, this implies you’ll be able to run the Software from just about wherever that’s at present mounted.
Notice: Some purposes might moan and pop up a dialog stating that they need to be run from the present “official” Purposes folder of the at present operating OS, however often that may be ignored.
Set up from package deal
Nonetheless, purposes put in utilizing a package deal (i.e. by opening a .pkg file) can’t be simply moved or copied1, and it’s best to re-install these accurately (utilizing the package deal) on the brand new OS drive.
Footnote
1 It is because packages often set up varied (and presumably quite a few) recordsdata in a number of locations and with out rigorously analyzing the set up log file, it’s a ache to maneuver the entire particular person recordsdata of their disparate locations, to the corresponding location on the brand new set up.
