You can mix luster dust with all of those, but I'm not sure why you'd want to. As a dye, it's probably not your best use of the powder, because you'd need a lot of it. You also won't get that shine you get if you brush it on after the fact. I've never tried it on piping gel, so I don't know the effects. It won't change the taste, may change texture, because it may cause clumping, and no funky reactions, that I know of.
What are you trying to do? and maybe someone can help you get the look you're looking for.
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