[Opinions] The French one, Clemen-TEEN
And it would be the form I'd use, since the name is French to begin with. Also, it is less associated with the song.
But I suppose Americans pronounce it Clemen-tyne.
"But it’s all right now.
I learned my lesson well.
You see you can’t please everyone
So you got to please yourself."
Rick Nelson, GardenParty
"It does not become me to make myself smaller than I am." (Edith Södergran 1891-1923)