Yes, I know I'd have to have our engineer back up target instances before importing, and first we'd try importing back to the sandbox, especially if we can do that to a different target, rather than first deleting or renaming our existing workflow.
A couple of months ago, we had our sandbox refreshed from production, and the workflow in question is associated with a the same test project on both instances.
I've already manually matched all the custom fields and screens used by the workflow. We have no need to overwrite either component, although, since the sandbox was in fact refreshed by test, there may be no consequence in overwriting.
We've successfully exported and imported the automations used by the workflow, so we know that will work.
We do not want to migrate issues--just the workflow. We could manually duplicate the workflow changes in production, but I estimate it would save at least a couple of hours of work, and mitigate the chance of error, to do an export/import.
So far, information I've found on the Internet, has not seemed to address our particular requirement, but I'll keep searching.
Update:
My admin colleague found a recent Community post that indicates there is no current solution. View > Export > marketplace displays a message that lists the transitions, validations, conditions and post-transition actions (=most of them) that won't be exported, and export to XML seems to be irrelevant because there's no function to import it,
I'm fascinated (and other responses) that the app has been offered, accepted and used, ever, with this limitation.