I'm sure there are those who choose to believe that because it fits their agenda rather than the facts. I'm afraid, however, you are going to have to blame Saint Jerome for the error, not those translating his Vulgate into English or German.
He (הוּא) in the original Hebrew is masculine. It is pronounced hoo and can also mean it. In the Septuagint, however, it was translated as autos he, indicating that the passage should be understood as a Messianic prophecy about Jesus Christ alone crushing the head. He [Jesus] will crush the serpents head.
However, St. Jerome in his Latin Vulgate translation made a major error changing it or he into she using the feminine pronoun ipsa instead of autos in the Latin. Roman Catholic scholars who accepted the Latin Vulgate then translated Genesis 3:15 in their Douay-Rheims Bible as:
"Inimicitias ponam inter te et mulierem, et semen tuum et semen illius: ipsa conteret caput tuum, et tu insidiaberis calcaneo eius."
I will put enmities between you and the woman, between your offspring and her offspring. She will crush your head, and you will lie in wait for her heel.
The Neo-Vulgate (Nova Vulgata), the revised Latin version authorized by the Vatican, corrected the error and changed it from ipsa to ipsum in the Latin.
ph