When I was a young child, my parents were avid mushroom hunters, and we would often have Morels and the Oyster mushrooms, plus “inky caps” that grew in the side yard.
My dad figured out a way to dry out the oyster mushrooms, then they could be used “later”. I don’t know the details.
We usually seal them in the Seal-A-Meal and freeze them. I’m only going to fry them up in BUTTER anyway, along with steaks, or use them in a quiche or casserole.