@Wayne-TP 

Thank you for your reply. Unfortunately it does not work that way, because it's not possible to select the doorbell as a trigger in the first place. I tried to describe that in my post. However, since I was not allowed to add any screenshots, my description may not have been sufficient. I try it again here. As you may see, there are no actions to choose from.

Hello @Wayne-TP ,

Thank you so much for getting back on this topic.

Tapo app is version 3.15.112

Google Home app is version 4.3.56.2

However, I do not know how to see the registered region of the accounts. I assume it's Germany for both but I have no idea how to verify that. Maybe you could give me a clue, where in the apps I could see that?

Thank you for getting back to me with this  @Wayne-TP .

It took me a while to answer after I tried to set up the Nest Hub in the way you proposed.

I created a new automation "Haustürkamera zeigen" [Show door camera]. The Trigger [Auslöser] is set to the doorbell ringing. The action I have set up is the command "Show door camera" [Zeige die Kamera von der Haustür]. This command is the very same that I use when I talk to the nesthub. The automation is set to play on the nest hub.

However, the automation is not working. When I play the automation from the phone, the display lights up for a quick glimpse, and that's it. When the doorbell rings nothing happens either.

For a better understanding a recorded both, the working voice control and the not working automation.

I hope there is a solution. Because obviously the communication between the tapo door bell works but the automation does not. So maybe I am just missing something.