In France like many other countries, electronic invoice will be mandatory as of 2024.

it will be supported in D365 for Finance via RCS and Electronic Invoicing. However, it is only supported for CLoud deployments.

For on-premise deployment customers, it is not possible. They pay for support and maintenance and must also have the possibility to receive these regulatorry features.

As a general question, is there a possibility to use RCS for Onprem deployments?

For this specific point, any possibility to integrate French electronic invoice for onprem customers.