I am using Paypal for recurring payments and they charge 8.4% fees for billing my clients $19 and converting it to EUR.
Hmm, the conversion is probably the issue here.
As far as I'm aware, Stripe and Paypal charge a flat rate of 2.9% + 30¢ per successful charge as long as you're doing under $1 million in volume per year.
For international transfers, you might want to look into https://transferwise.com/ or companies that use their technology for international transactions.