I think one could get a bit of an alloy melting Ba and Co together, but I don't think they dissolve in each other when liquid. An alloy can still be made by taking a suspension, one might have to continually agitate it, then splat cooling small blobs of the mixture. Metals cooled superfast tend not to crystalize, but atoms just freeze in place.

It's hard to get reactions with N, because it's always tightly bound in an N2 molecule. It's much more reactive as a nitrous group, NO2-1 or nitric group NO3-1. In H2O these go to nitrous acid HNO2 and nitric acid HNO3 or a ammonium group NH2-1, etc.

I think with a catalyst to break the N2 at a lower temp, the BaCo amorphous solid could be burned in N2 at a low enough temp that the Ba and Co don't start recrystalizing and basically fall apart. The result might be some Ba3N2 and some CoN and Co3N2, but these combustion products might be like some metal oxides and just turn to powder. With luck one might get some flakes of amorphous BaCo with some sort of metal nitride "rust/corrosion" sticking to the sides of the flakes. At least they'll be somewhat flat, which would help in frying! Maybe one could bread these flakes first.