While the Cisco Meraki MX series can provide wireless capabilities, its primary function is as a security appliance, not as a full-featured access point like the MR series. This means that while it can broadcast an SSID, it doesn't support more advanced wireless features, including mesh networking.
For seamless wireless coverage and signal handoff, you would need multiple MR devices. In this case, you would configure one MR33/MR44 as a gateway (connected to the MX device via Ethernet), and additional MR33/MR44 devices as repeaters. These repeaters would wirelessly connect to the gateway or other repeaters to form a mesh network.
By having all your MR devices broadcast the same SSID and configuring them correctly for mesh networking, client devices should be able to move between MR devices seamlessly without losing connection.
I hope this clarifies your question. If you have more questions or need further guidance, please don't hesitate to ask.