Payment Service Directive 2 (PSD2) is the implementation of a European guideline designed to further harmonize money transfers inside the EU. The ultimate goal of this directive is to simplify payments across borders so that its as easy as transferring money within the same country. Third parties often live under a separate set of rules and are not always subject to the same scrutiny. The European Banking Authority published guidelines on the information to be provided by applicants intending to obtain authorization as payment and electronic money institutions and to register as an AISP.”]
Source: https://blog.malwarebytes.com/security-world/2019/03/explained-payment-service-directive-2-psd2/