I have a Meraki MX84 in Routed mode with a Default 10.10.0.0/24 subnet and then VLAN 10.10.3.0/24 ID 3, VLAN 10.10.4.0/24 ID 4, VLAN 10.10.5.0/24 ID 5, and 10.10.8.0/24 with ID 8. All ports on it are set to Native VLAN 1 and Trunk I have a Cisco SG200. I've added the VLANs 3-5 and 8. All ports are set to Trunk.
The MX is in port 1 of the SG200 and I set the Administrative VLANs to 1 and 5. I have PCs on 10.10.0.0 and 10.10.8.0 and then a server uses the other subnets and need them to connect with each other. There is no reason to keep the subnets separated.