Follow up / SOLVED
After a lot of research and trial & error, i figured out devices are exposed and shown in devices in Google Home, and scenes are only shown when you add an action in a routine in Google Home.
So far, so good.
But even though I would add a trigger like “Kitchen Lights On”, it would not work … Instead Google Home would turn on a device called Kitchen Lights Zone 1 or something simular.
I then removed all devices from Expose to Google Assistant in HA so that I only had my scenes and now, since Google could no more match with a random device it works.
Note. Don’t use () in the names of devices or scenes exposed to Google, they will not show with the correct name.