Ensure the rus_payments add-on is installed (dependency).
In add-on settings (Add-ons → MS Legal Person Lite), enter the API key for dadata.ru if needed — without the key, INN autocomplete is disabled.
Enable or disable the desired fields (organization, bank) and options: "Show field when paying", "Show field in invoice", "Required field".
Configure the "Invoice" payment method in Administration → Payments: add a payment method based on the add-on processor and fill in the recipient details (name, INN, KPP, address, phone, etc.).
Usage
At checkout, the customer fills in organization or sole proprietor details; when entering INN or name, data may be autocompleted (if the DaData API key is set).
After the order, invoice print (PDF) and emailing the invoice are available (if enabled in add-on settings).
In the admin order details, the entered details and the print invoice button are shown.