Not sure what you want to achieve here, but you can’t connect the Bose to Arc Ultra via bluetooth. The Arc is a bluetooth receiver and not a transmitter - it connects with the Sonos Ace via WiFi.

By the way, connecting the Bose via Bluetooth to the TV will only work when HDMI-CEC is turned off temporarily. If not the Arc Ultra will take the connecting back.
 

So if you want to use a headphone with your TV and it has a Sonos soundbar connected, best advice is to buy the Ace.