In short -Endnote can’t do this automatically.
But word does have a way to Cross-Reference in footnotes (Ifound this tip here andMicrosoft’s site has this). I don’t work with footnotes and haven’t tested the efficacy of this trick though.
So I guess you would insert the footnote in Word, add the endnote citation for Smith, and then use word again to add the cross-reference.
You would also need the short form of the footnote to be just the Author, I assume. If you deleted the original footnote, not sure what happens next though. That would be MSWord’s problem… and you might have to clean up the parentheses in the footnote.