Help with payments on bubble

Hi there.

I am building a marketplace and am looking for a method to process transactions whilst taking a fee, I am based in the UK. I have tried to use stripe connect, however this requires sellers to sign up which is quite complicated. Is there a simpler method? Something like paypal would be ideal.

I would be grateful for a step by step process on how to do this. Ideally, the seller would not have to leave my marketplace. Any help is appreciated