The unit is just a comms module i.e. it would need a controller like the Atom Lite. In terms of connecting to HiveMQ it could be used to send out MQTT requests. Perhaps you could expand what you are trying to achieve.

If you have many devices (taking to mean sensors) connected to a Atom Lite controller then this could gather readings and send from a single Atom Lite plugged into this module.

If you have many devices (taking to mean Atom Lites) and you want to concentrate to a single mobile access point. It could probably be done by connecting one Atom to a 7080G unit and then relay from other Atom Lites, but a commonly available Mobile Hotspot (e.g. 5G) device to connect all the Atoms via Wi-Fi would probably be better.

The benefit of this device is its low power consumption and design for mobile data at relatively low volumes (see LTE-M and NB-IoT).

As an example, I have a Core2 and IoT base configured to simply request the current CO2 from electricity production once a day and display it. The SIM costs are minimal a few pounds per year, not per month. It is completely standalone, apart from power. For example, I have used it to collect button presses on a micro: bit via serial and relay them to AWS.