Well, then that’s your root problem. The zwavejs2mqtt add-on is conflicting with the zwave-js addon and causing the devices to become unavailable. You need to verify which add-on the integration is communicating with before deciding which add-on to remove.
If it’s configured for the Z-Wave JS add-on, then you’ll need to follow the instructions to switch to zwavejs2mqtt. See integration docs (and/or guide).
If it’s configured to talk to the zwavejs2mqtt add-on, then you just need to delete the Z-Wave JS add-on.
I’m not sure this is possible. Probably at best you can add a link to it in the side-bar. Fix your root problem and I suspect you won’t need do worry about it anymore.