Anyway, for future...post also the sollution! Maybe someone will search and need to see the results!
For somebody who search for this, the sollution is:
1) Create the bridge on eth1 (on second NIC) - will be vmbr1
2) Create the KVM machine, and after that go into the the "Hardware" tab and on the top left arrow select "Add an ethernet device".
See wiki for more details!