I know how to change icons in Finder by pasting them into the Get Info window.
But this doesn't work for Network devices.
For linux shares for example, this can be added to smb.service for avahi so MacOS will assign the Xserve icon to the share.
<service>
<type>_device-info._tcp</type>
<port>0</port>
<txt-record>model=Xserve</txt-record>
</service>
How could this be done for another MacOS share on the network? For example, make my Macbook's icon appear as an AppleTV?
They are not themselves drives, and as such have no filesystem to attach an icon to, it would have to be done via an smb setting to spoof the device as if it were another kind of Apple device as laid out in the linux example.