How about "in-shoring"? We already have "insuring" and "ensuring", so we might as well add another confusingly similar sounding term to our vocabulary.
Corporate has been using the term "best-shoring" for a couple of years now. To my best guess, it means "off-shoring or on-shoring, whichever of the two is cheaper".
I thought "on-shoring" is already commonly used for the process that undos off-shoring.