Have not been able to get this to work (yet) starting to wonder if it is even possible...
Multiple buildings each with a ms210 connected with MR74 back to the main office. we segment vlans based on device/traffic type ( MGMT,Data,Camera,Voice...) each building will one or more of each device type.
The gateway access point may be configured to connect to a trunk port and trunk SSIDs to different VLANs. Repeaters will also serve SSIDs trunked on different VLANs. However, only one SSID & associated VLAN may be configured to bridge wired clients across a mesh link on a repeater access point's Ethernet port. A mixture of wired clients and Cisco Meraki access points attached to one MR repeater interface is not a supported deployment configuration. This is due to the auto detection mechanisms that Cisco Meraki access points use to infer when they should function as a gateway or a repeater.
To make this work you need to put each MS210 into layer 3 mode. You ideally want to put the bridged network into a single unqiue subnet - this will be a transit network. Each site will end up having its own unique subnet for each VLAN - rather than being an extension of the main site.
So all traffic to and from the sites is routed - not bridged.