Kresser also mentions Elderberry and Licorice Root among other things for colds and flu.
https://chriskresser.com/the-top-20-natural-remedies-for-cold-and-flu/
Things like: Andrographis, Manuka Honey, Propolis, Colostrum, Chinese Skullcap, Echinacea, Elderberry, Garlic, Ginger, Houttuynia...