Note: Only Cisco Meraki APs can function as repeaters and gateways. Wireless MX security appliances, Z-Series teleworker gateways, and third-party APs cannot participate in a wireless mesh
Sorry no, the mesh repeater links are only formed between Meraki APs being managed in the same Meraki Dashboard organization, not meant to interoperate with FritzBox or other residential style gateways or repeaters.