Ethanol is a great preservative, it works fine all on it's own, no need to add anything, just soak the mushrooms in the booze for a couple weeks to several months and filter out the biomass.
A touch of ascorbic or citric acid doesn't hurt, but it's not necessary. It's really more important in water based extracts, as I said ethanol is preservative in and of itself.
Honey is also a fine preservative and blue honey is quite a delicious way to take the medicine.
I would recommend to use either or, but not both, unless your goal is a mead-like honey liquor, in which case I would simply dissolve an already made blue honey into the ethanol.
Also please don't use heat to evaporate ethanol, that is asking for trouble. Just put it under a fan, it evaps just fine that way and quite quickly, and you don't risk burning your house down.
Be safe now