Hi,
If I buy ,from a third party a Business smart home 3 will it work on my home system.At the moment i have a smart hub 2 and I underdstand this business hub has wifi6
It does not support BT Digital Voice.
don't think it works with digital voice if you have that
You may have issues authenticating it, but as you have DV, then its no use. Probably best to find a separate wireless access point, or mesh which has Wi-Fi 6.
See https://www.tp-link.com/uk/home-networking/deco/deco-x60/