Русско-англо-русский юридический словарь

The underlying basis of an exemption for agent of a payee transactions under state money transmission laws, including the MTA, is that the intermediary (a marketplace platform, a billing service, a payment facilitator, etc.) facilitates the receipt of payment by merchants or other payees, rather than facilitating the transmission of funds on behalf of a sender of funds. (JD Supra)

remitter (also: remittor) – a person or company that remits or makes a remittance (Collins Dictionary)