There's lot issues.
1. Against
BetFair TOS.
2. Breaking the LAW (French Law)
3. I recently read that PC charges are by person not account (so commission versus profit is calcualted over multiple accounts if you have more then 1) {don't know about data charges}
4. Who ever opens the account for you will have to do deposits & withdrawals for you (trust??)
5. Tax implications in country residence

As I have said before you need someone you trust and trust you ... best if they don't even have a
BetFair account or interest in gambling.
Good luck with your searcgh.