A monetary ecosystem has developed in recent years transforming the concept of money and its statu quo. Complementary currencies (CCs) are types of exchange media that support the creation of monetary ecosystems. CCs can contribute to sustainable economic development as they connect stakeholders, strengthen community relations, and democratize the control over exchange mechanisms. In France, CCs have developed at the local level as complementary local currencies (CLMs) aiming to favour local exchanges and revitalize the economy of French territories. At the same time, the digital revolution is influencing present dynamics by dematerializing legal money and creating new forms of value, such as virtual currencies. Nevertheless, legal issues exist with regard to this monetary diversification, such as the legal recognition, sovereignty and convertibility of these types of currency systems. This paper focuses on the legal aspects of monetary diversification both in the local and virtual realm, and analyses the legal framework and benefits.