your ornate is definitely too small to breed, and when it reaches breeding age, it wouldn't be interested in the senegal anyway due to size difference. So i don't think natural cross-breeding between these two would happen. But i think it's safe to say that any species can hybridize with any other (even if they don't do it naturally), given the different hybrids that farms have produced so far.
and as for sexing, you can tell ONLY when the fish starts to mature. young bichirs cannot be sexed, as they'd all look like females.
