Hey I'm on CD but I can help with DIM. DIM is a known anti-estrogen. It's been shown to increase estrogen metabolism in the human body 3,3′-Diindolylmethane Modulates Estrogen Metabolism in Patients with Thyroid Proliferative Disease: A Pilot Study Essentially, DIM will help clear out estrogen faster from your body (but will not stop its production). It can be helpful when trying to reduce estrogen levels.
Unfortunately, for something like gynecomastia, you're going to have a hard time getting rid of it without an AI or SERM. That can be pharmaceutical or otherwise.
Iron Legion has Virtus which is a topical anti-estrogen
From a forum sponsor: virtus - socal-nutrition
From the manufacturer themselves: https://iron-legion.com/products/virtus
Per this study Synthesis and biological evaluation of 4-imidazolylflavans as nonsteroidal aromatase inhibitors - PubMed this compound was found to be only 2.2x less potent than the pharmaceutical letrozole which is used by many to get rid of gynecomastia.