Probably unlike even Julian of Norwich (whose own twentieth-century transformation into a mainstream figure nevertheless deserves far more criticism than it has received), contemporary proponents of Mother-God language, such as the new Presiding Bishop of what remains of the Episcopal Church in the United States of America, do not wish to preserve any sense of the "Otherness" of God.
On the contrary, they wish to draw little distinction even at the most academic level, and none whatever anywhere else, between God and the Universe, between the Creator and Creation, despite the Universe's being fallen, which they therefore seek to deny, thus subverting any concept of objective moral evil. It is held that, since the human person is part of the Divine Universe that is the Mother-Goddess, so the human person cannot sin.
Related to this, they also hold that what they are pleased to call "gender" is fluid, culturally constructed, relatively unimportant, and even self-defined by the individual; if anything is innate, unalterable, and fundamental to identity, then it is the homosexual, heterosexual or bisexual "orientation". Therefore, the debate around such matters is a debate, not only about doctrine, but about the ontology dependent on doctrine and on which doctrine depends.
When a woman exercising episcopal functions is addressed as "Mother in God", then she is proclaimed as the icon of a Mother-Goddess at least including, if not actually identical with, the material universe, within which sin is impossible, and the two sexes are interchangeable, but the fundamental ideological concepts of homosexualist politics are abolsute and non-negotiable. And when some among the twenty-six per cent of the Church of England's women clergy who were shockingly found not to believe "in God the Father Who created the world" quip that they believe in "God the Mother", then, as they themsleves might put it, that is what they are affirming. The rest of that twenty-six per cent are presumably atheists or agnostics.