I'm from Germany, but that's also European Union. Under the common law it
is allowed to import any fish or fish parts - like eggs - if they are not listed in
the species protection convention. As the EU convention has taken over the
CITES list, there are no Australian fish except Neoceratodus and Scleropages
on this list. The worst thing which can happen that the French customs ask
him to have a veterinary look at the fish and declare they aren't ill. However,
that will surely happen in Germany sometimes, but I don't believe that happens
in France (we have a lot more bureaucracy).