(RESOLVED) Why doesn't this procedure spawn particles or play sounds?

Is it not because you use source entity instead of event/target entity?

Not sure, but if it works like intended thats good. Then for the sounds and particle you should just be able to swap the X Y Z with X Position of Source Entity Y Position of Source Entity and Z Position of Source Entity. 

Weird, I will try to recreate something tomorrow and see if i can make it work. I would like to know your Minecraft version though

I recreated your procedure like the image and it did not work for me even, I need to know if the off hand item is supposed to be dropped or follow the player after death? 

In any case, i think the "(sub)entity" with "entity dies" is bugged, so we need to use "entity exist" instead, I made this procedure instead

Now this replaces the emerald with the diamond, it just drops it so the player has to go pick it up but i think that is how you wanted it right? Hope it helps!

Yes, the procedure was tested and everytihng worked like you wanted, just copy it. It works the same pretty much

Awesome! My guess is that (sub)entity with entity dies is simply just bugged, might be fixed or not, but this works in the meantime, as using commands only works if the player has admin status