Two IP-Ranges on one interface - can clients talk to each other?

Hi,

I'm trying to figure out if it is possible to combine two interfaces into one.
Right now I have 2 interfaces on my asg with local IP addresses of eth1: 10.10.0.1/16 and another interface eth2 with 192.168.1.1/24.
There are a couple of clients connected to each interface with IPs of the corresponding ranges talking to each other accross the asg.

What I would like to do is combine those interfaces into one. So I would add the IP of eth2 as an additional IP of eth1 and connect the switches that host the clients to this one single interface. Will clients of both ranges still be able to talk to each other or is this not possible on the same interface?

If that dowsn't work: how would you do it? I cannot change IP addresses of some clients as they are hardcoded in some software that noone is able to change in a reasonable timeframe. But since all those clients are on an "internal" network anyway and I need another port on the asg for more important separation I'm trying to free up that port.

Thanks for your thoughts.
Chris