I suspect there are a number of operators and airlines that would give employment preference to an Australian trained pilot.
I suspect a few Australian pilots would agree with that.
Common sense would suggest that training and flying in different countries and qualifications from more than one jurisdiction indicate a depth of experience that would be respected and in demand.
Unfortunately in Australia you are sometimes better off not drawing attention to such experience. It seems many of those operators and staff in airlines who make the decisions on such matters have limited to no personal experience of flying outside Australia.
The last I heard was that it is still the practice in some Australian airlines to require completion of all Australian ATPL subjects and possibly even initial ATPL issue to be from CASA. Has it changed ?
Fud