Adblock for specific devices, tutorial to create multiple dnsmasq instances?

Yes, there is an experimental/undocumented option 'adb_dnsinstance' ... '0' is the first instance (the default), set it to '1' to catch the second instance. Before you change that value, please stop adblock so that the old serversfile entry will be removed, than put ...

option adb_dnsinstance '1' your global adblock config and restart.