I spent some time looking at making an FDM machine that would print bronze filament. An alloy commonly made into wire had a difference between the solidus and liquidus temperature of only 50 degrees C. I determined that one could make a conventional hot end, electrically heated, made of either molybdenum or tungsten.
I did not determine how the bronze would behave in the 50 degree solid-to-liquid zone. I was more concerned about the solubility of the nozzle material in copper, for which I could find very little published data.
From my experience welding, and from printing plastics with FDM, there could be a problem with layer adhesion. To really bond, the cooled material needs to be melted by the material being deposited in the next layer. This is complicated by the temperature of the cooled material, the thermal conductivity of the material, and the propensity of the material to form oxides. These could be mitigated by heating the object in an inert atmosphere.
So, to answer the question, I would suggest looking at bronze alloys because they melt at moderate temperatures, and are less prone to oxidation than aluminum alloys.