I’ve started going down a similar path for scent and ADHD. I have a horrible sense of smell and just learned that it might correlate with symptoms of ADHD.

Interesting. Research results seem mixed, and I wonder if ASD comormidity is affecting them. https://pmc.ncbi.nlm.nih.gov/articles/PMC7369237/ has a reasonably large sample size and finds an effect for ASD but not ADHD.