Don here from Shopify. :)
Thanks for taking the time to post your requirement here on our merchant forums.
It looks like none of the available credit card gateways (2Checkout, Paytabs or MOLpay) are actually direct gateways here so they would require your customers to check out external to Shopify.
As these gateway integrations are created and maintained by the gateway companies if you would like to request that they instead create a direct integration here you would need to contact your gateway of choice to see if they would be willing to do so.
All the best in any case!