Yes, FW threads did come in several varieties, French, Italian, English. Most are English. Italian has the same thread pitch and diameter but a slightly different angle on the thread profile. You can use Italian or English on any Italian or English hub but it is best not to go back and forth. French threads will not fit either.

A Maillard hub may or may not have had French threads, as many were made for other markets. Also for a while they had they own system called Heliomatic, or so I understand. I know nothing about it except what I've read here in BF but I understand they can be problematic. I don't know if the difference was in the threads or in how the sprockets were attached.

Anyway, your best bet is to find out from the seller what threads it has. If it is Heliomatic I'd probably look elsewhere though I'm sure someone here would know more. If you like those wheels but the FW threads are different, you can find FWs easily and cheaply enough. But you gotta' ask.