To support cross-site connectivity in a production Multi-Site solution, where connectivity from EPGs from a specific site to networks reachable through a remote site L3OUT is required, the additional configuration that must be implemented in the Multi-Site Orchestrator is to add a new stretched external EPG to the existing L3OUT1. This allows the EPGs from one site to communicate with the networks defined in the L3OUT at the remote site, facilitating the required connectivity across sites.

References :=

Cisco ACI Multi-Site Configuration Guide1