Multiple references for the same payment gateway

it’s doable, but it’s not something you can just configure with the out of the box interface. Basically, you have to duplicate that payment gateway class inside a separate plugin, give it a different class name (or possibly extend the existing class), and change the option_name value(s).

After that, you need to use a filter to programatically disable the payment method you don’t want used based on what is in the cart. Also, you definitely can’t do split payments, so you’d need to control what can be added to the cart together…

If your market is such that one is not likely to buy more than one thing, or at least from more than 1 vendor, then this might be viable, but otherwise, not so much.