I am working on a project magento 2.2 and client to show only Credit/Debit card form (backend connected with paypal, means we can use Paypal Express Checkout)

But client want not to show list or event Paypal Express Checkout as a payment method but client want to show that Popup occur on that page. (having option to log-in with paypal or pay with debit/credit card)

I have tried custom payment extension by webkul but it didn't work.

One more way I have in my mind, that what if I show that Paypal popup in an iframe instead of list of payments.

Will it workable ?