Watch This Space, page-6302

In a nutshell, Mastercard provides BNPL flexibility.
Either the merchant or the payment service provider (PSP) interact with MC to process installments.
In-order to do that the merchants should use an in-house implementation or a PSP which has the MC BNPL API integrated.

Here is the list of PSPs : https://www.mastercard.us/en-us/business/overview/start-accepting/payment-facilitators.html

Splitit can approach the PSPs , offering their service as white label.
Merchants can directly on-board Splitit.


Bottom-line: Yes MC provides BNPL option, but it cant be directly used by merchants as-is.

Others feel free to correct my understanding, if mine in wrong or if had missed any nitty gritties.