First and foremost, research suggests maintaining a healthy body weight. Choose foods that are higher in fiber to help bind bad estrogen to remove from the body. A lower carb/sugar diet is recommended. Eating plenty of cruciferous veggies like broccoli, cabbage, kale, etc. I would avoid soy and foods with phytoestrogens (flax) as the research on these has been inconsistent. Foods high in antioxidants (think dark rich colors: reds, oranges, yellow, purples, and greens).
Eating simply and mostly plant-based shows to be beneficial. You're on the right path!
Remember the other areas of wellness...stress management, exercise, social support and rest!