Cantonese is used in Hong Kong. Croatian and Afrikaans are presumably useless too. Maybe extended mode or playing as KGB or Mossad get different cities. I'm playing as CIA.
Croatian is used in Dubrovnik. I also play CIA, so if you don't see yet it you will soon enough.
I noticed KGB definitely starts with different cities, but I think that eventually everyone gets access to everything, just in different orders - though it wouldn't surprise me if extended mode has even more than regular modes never get.
I suspect Portugese will be used for Lisbon - while I haven't unlocked it so far, this city was famous for espionage during the Cold War, so I suspect it will appear at some stage, even if it's only the extended play through.
I would have expected Afrikaans to be useful somewhere, given how during the '80s (at least in RL history) a lot of weapon dealers and mercenaries came from South Africa. Maybe it will also pop up later.