I would suggest that you simply make a donation to whatever charity you like and not tie it to any specific listing.
For example all the proceeds from the sale of my patterns go to various charities but I don't specifically mention any charity in the listings nor do I advertize the fact (other than one small mention at the bottom of the listing).
If you are going to donate from a specific listing and mention the charity in the listing, you will need to follow the rules for charity giving
https://www.etsy.com/help/article/4528?ref=help_search_resultincluding having permission from that charity to use their name in your listing(s).
You might be much better off simply to make a donation directly to the Red Cross or whatever charity you choose.