@auksst @auntieoakley @monigue @ptown :
When looking for and evaluating complementary therapies, I usually turn to NIH's National Center for Complementary and Integrated Medicine (NCCIH) website https://nccih.nih.gov/

In the section "Health Topics A-Z" current therapies and conditions are listed explaining the most recent evidence, cautions and potential of future studies.

Here is their information on
- Black Cohosh https://www.nccih.nih.gov/health/black-cohosh
"The research is inconsistent on whether black cohosh helps to reduce hot flashes that are related to breast cancer treatment. People with breast cancer should avoid using black cohosh before talking with their health care provider."

- European Mistletoe https://www.nccih.nih.gov/health/european-mistletoe
"European mistletoe is not a proven cancer treatment. It should not be used as a treatment for cancer outside of clinical trials."

Additionally, here are the search results on NCCIH for "hot flashes" https://search.usa.gov/search?utf8=%E2%9C%93&affiliate=nccih&query=hot+flashes&searchsubmitbutton=