Changing to a new Home Assistant Connect ZBT-1with 41 existing devices

Well, I decided to purchase a Home Assistant Connect ZBT-1. I received it today and I am thinking about the process to install it and get all the devices to connect with it. I am pretty sure that I will need to pair each of the 41 devices individually. Can I leave the existing dongle connected and move each of the devices over the next few days or so? I am wondering if the devices that I move to the new ZBT-1 will work with the existing devices on the old dongle. Also, will there will be an issue with the Zigbee mesh setup. Maybe an issue there.
Thanks