Just to avoid confusion, in order to isolate assets in the way you described, you'll need multiple licenses (one for each site). The Lansweeper data will always be stored in one database, meaning that even if you have multiple scanning servers, they will all send data to the same database, and people can view all the assets in that single database.
This particular feature is already on our list of thing to do in the future. However, I've added your topic to the list of people requesting the feature.
Since there is no way to split asset permissions based on site, there is also no need for multiple LsAgent keys per installation, since all assets are in the same database anyway.
If you have a multi-scanserver installation, and you are using a direct connection (so no relay server) you can choose which scanserver is tried first, and if there are any other scanservers that should be checked afterwards if the first scanserver connection fails.
![linked direct scanservers](https://i.imgur.com/BbtoJXm.png)
If you are using the relay, you can choose which scanning server is used to fetch the data from our cloud server.
![cloud relay config](https://i.imgur.com/yyayyh0.png)
If you do have multiple licenses, one for each site, you can request a cloud relay key for each installation and simply use the correct relay key with the correct LsAgent installations.
I hope this clears things up