Hello @EnterpriseArchitect Thank for posting in Q & A forum. It's possible as long as the routing is sorted from Connecting Azure to on-premises networks and returning from on-premises networks to Azure. On the "Azure part" of the configuration of the vnet peerings, there are two helpful options: "Allow Gateway Transit" and "Use Remote Gateway". We can connect an ExpressRoute circuit to multiple virtual networks. See Subscription and service limits for the maximum number of virtual networks that can be connected to an ExpressRoute circuit.
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