We want to implement the following topology :

INVITE--->kamailio1-----forward--->kamailio2--->route[NATMANAGE]--->Next Sip endpoint

Client <---- route[NATMANAGE]<--------kamailio1<------forward-----kamailio2<---- reply with SDP

So the caller to callee will be processed by one kamailio and callee to caller will be processed by another kamailio. Both kamailio will be up with a public IP. How this can be achieved?