You do not need to speak the french language but you should make all "standard" circuit calls in French.
Should one really? Where is the obligation? If not calling out at all, what law/rule will be violated?
But yes, I know, among the few fields in France that announce "FR only" there are a very few that also announce "carriage of radio mandatory". "Carriage", mind you, not "switching on" even less "listening" and even even less "talking". A bit of an ambiguous situation, I would say. I have no idea of the situation in the Caribbean but I'd not be surprised if there, even more than in "France Métropolitaine", much or even everything would be left to pragmatism and the basic principles of "good airmanship". Which is luckily undefined in law, as far as I know.