I had a PSA 10 mothra that I sold last year. I put it up as a BIN for like 120$ish. I had 4 offers within the first few hours and then someone just bought it outright before I even reviewed the offers.
It was technically a set card, not a promo. With that said I don’t think the Dracula cards for example would be worth grading. I also have a set of CGC 10/pristine junji Ito promos in foil. No idea what they are worth, but stuff like that might fetch some sort of premium.