@Will2209 It's a terrible idea that will not pay off for you in anyway. Self-proclaimed "influencers" may appropriate images of your home to enhance your personal brand, but it's virtually implausible that this exposure will convert to actual bookings.
If you want to give someone some kind of discount when they send an inquiry, there's still the "Special Offer" function you can use. But don't be shocked if they wind up demanding more and more free services and ultimately leaving you with a huge mess. That's the typical result of this arrangement.
Donations of a free stay for actual charity get routed through the Open Homes project: https://www.airbnb.com/openhomes
Read the fine print, of course. Many hosts have reported their charity being abused, and Airbnb won't be much help if the arrangement goes wrong. Whether it's for promotion or philanthropy, you've got to consider whether you'd rather stick with people you know and trust, or take a hail mary with strangers from the internet who want something for nothing.