Hi,
This is more a general question but cannot find a better place for it!
Basically a few rooms in the house have blinds installed + have a Google Home present. In each of the rooms, I would like the phrase “open blinds” or similar to open up the blinds in the specific room.
Is there a way to achieve this? Similar with light on/off command, would like to have a universal one that has a different reaction based on which Google Home device issued it.
I know in Google Home you can create rooms and put your devices into rooms. That is how you make Google Assistant aware of what room a device is in. Note, you also put your Google Homes into the various rooms so Google Assistant knows what room you are in when you issue the command.
I think that lets you issue a command like “open the blinds in here” or “open the blinds in the living room” to open the blinds in another room.
See Connect third-party smart home devices in the Google Home app - Google Nest Help for setting up the rooms.
Though I admit, I’ve set all this up but I’ve never actually used Google Assistant like that. So I can’t be any more specific than that. And I do know there are differences in languages where some features are not available in all languages.
@rlkoshak gave the better answer, I guess.
But as a workaround befor openHAB/Alexa supported rooms I set up my system like this:
// Harmony Activities
Switch Alexa_Radio "Radio Wohnzimmer" [ "Switchable" ] {alexa="Activity", autoupdate="false"}
Switch Alexa_RadioPC "Radio Arbeitszimmer" [ "Switchable" ] {alexa="Activity", autoupdate="false"}
Switch Alexa_RadioBK "Radio Badezimmer" [ "Switchable" ] {alexa="Activity", autoupdate="false"}
I simply added the room name to the item name. 
Not perfekt, but it works.
I can only confirm what @rlkoshak said.
I have my roller shutters assigned to separate rooms, so when I say “open shutter(s)” only the shutters in the room of my Google Assistant device that answers (usually the closest device) open.