I already replied to your support request. To my best knowledge ESPhome proxy and a BT adapter should be equivalent from the point of view of this integration. So there is no need to have both.
Not in all cases.
Only one of my Batteries have a Bluetooth Module but that one is the Master of the 5 Packs. They are all connected via RS485. In the Manufactors BT App i can see all 5 Modules named BP00/01/02/03/04.
I’ve Thaugt your integration works the same.
Probably not…
I bonded the MAC-Address via Bluetoothctl and it looks like that the connection will keep up. But HA shows just not available instead of the data.