I'm going to give the below-listed module a try -- I'm absolutely flabbergasted with PS checkout requiring someone to fully check into your site during checkout, even though it's supposed to be a 1-page guest checkout. In fact, it's actually really rude and turns off the customer. Checkout on PrestaShop should be a simple, fast and hassle-free process. When we're telling our customers that they don't have to register -- but then they're denied payment options before completing checkout - how do you think it makes them feel?? C'mon PrestaShop. Get with the program. Stop giving excuses and start listening to what we've been saying.
https://codecanyon.net/item/show-payment-methods/14156779/comments