WooCommerce

In many countries a national identification number, individual taxpayer registry, identity document or any number used to identify citizens on government databases is needed to shop with credit card and is important to add this feature added to WooCommerce core, along with date of birth.
It can be:
Social Security number (USA)
National Insurance number (United Kingdom)
CPF number (Brazil)
SNILS (Russia)
Social insurance number (Canada)
INSEE code (France)
PPSN (Ireland)
Tax file number (Australia)
Aadhaar (India)

In many countries it is a mandatory field on the checkout page (usually along with date of birth).
Almost each of the cited countries use local plugins, but it relays in voluntary work and are not updated. The (only) one that exists in Brazil (90000+ active installations), for example, is 5 years old and it is not compatible with block checkout
Of course there is a general plugin to add custom fields to the checkout in the market, but it does not work well for this specific case.