Thanks for your replies!
What kind of prepaid cards exactly ? You mean a card where you can add BTC and pay Euros or a just a bank card you can top-up ?
Any European or American prepaid card would work in France.
I'm looking for the type of cards described in this thread:
https://bitcointalksearch.org/topic/m.12360185
Like this french card:
https://bitcointalksearch.org/topic/m.12174144
https://bitcointalksearch.org/topic/m.12080977
Do you know other similar cards?