While the Emacs wizardry is very nifty, it might be better to use the csquotes package, in which case you could have done a query-replace changing emph to enquote.
– joost 2021-02-20 13:10 UTC
Thanks, and yes, I was aware of such an idea (though I forgot about that package). But my main goal here was to show a nice Emacs trick, of course.
– mbork 2021-02-20 16:26 UTC
I know, and it was quite impressive. 
– joost 2021-02-22 08:05 UTC
Thanks!
– mbork 2021-02-23 17:28 UTC