5alpha-R type 2 is controlled by T (at least in rat brain).
https://pubmed.ncbi.nlm.nih.gov/9699883/
The mechanism of finasteride-induced effects on mood and behavior are fairly well characterized, that is, they are very likely a result of decreased neurosteroids. In men, 1 mg finasteride was associated with a decrease of 5α-reduced steroids, especially of allopregnanediol, DHT, and pregnenolone, and this decrease is related to depressive symptoms (in a small subset of men) as presents in the post-finasteride syndrome. See also:
Risk-reward profile for progesterone/allopregnanolone supplementation (I generally don't like supplementing these neurosteroids, but describe the tradeoffs ther