We have several Discovery rules on the same proxy with the same SNMP checks:

1.3.6.1.2.1.1.1.0
1.3.6.1.2.1.1.2.0
1.3.6.1.2.1.1.5.0

Device uniqueness criteria and Host name:

1.3.6.1.2.1.1.5.0

If the device is discovered in several networks Discovery actions will create duplicates with different IP-addresses:

hostname
hostname_2
hostname_3

In versions prior to 7.0 (even 6.0) Discovery Actions just add new interfaces to host for uniq host:

hostname
SNMP_interface_1: IP1
SNMP_interface_3: IP2
SNMP_interface_3: IP3