There is no hormonal side effect for humans consuming large quantities of soy.
https://www.scientificamerican.com/article/soybean-fertility...
So here are actual human studies with data.
Clinical studies show no effects of soy protein or isoflavones on reproductive hormones in men: results of a meta-analysis.[1]
Isoflavones made simple - genistein's agonist activity for the beta-type estrogen receptor mediates their health benefits.[2]
Soy food and isoflavone intake in relation to semen quality parameters among men from an infertility clinic. [3]
[1] https://www.ncbi.nlm.nih.gov/pubmed/19524224 [2] https://www.ncbi.nlm.nih.gov/pubmed/16513288 [3] https://academic.oup.com/humrep/article/23/11/2584/2913898