epassporte's site says that your bank may consider an epassporte payment as a cash advance. It probably varies by the policy of the card issuer, so you might want to call 2 or 3 times to your card issuer and ask the question of several different reps, as they're notorious for telling you anything and then taking no responsibility for it.

If you call 3 times and get the same answer each time, there's at least a 50% chance the information you get is actually correct

Also, keep in mind if you have an individual account, you can't load more than $500 per day to Epassporte.