Pretty sure this requires animation changes within m.dts which will never happen as long as Blockland exists...
if this isnt possible as an emote, why not make it an item?
give it a command such as /useprintgun or /wrench, so its in your hands immediately when you type that, so your hands go up. it would be kind of odd, but it would work perfectly.
there's guns that make your hands disappear and have hands on the model, so i dont see why this wouldnt work.