In the big three religions of today God is seen as a paternal All-Father ruling his flock with a more or less heavy hand. The omission of the Divine Feminine principal and the fact that the Goddess can be found in Wicca is one of the main differences in belief systems.
For people struggling with gender identity, the idea that God might be only masculine or feminine is an obstacle to understanding the true nature of how Wiccans view the Immanent Divine.
God in Wicca is a fluid construct. We have five pantheons of gods and their sacred stories holding energies and power like hidden jewels, that can be accessed through ritual and spiritual/magickal work. Whether you as a Witch resonate with the Celtic, Norse, Roman, Greek or Egyptian Old Gods, there will be certain sacred beings that call to you. We refer to this resonance as 'creating correspondences'. For example, if you are focusing your spiritual work on understanding love, healing and compassion you might connect with the presence of a Goddesses of compassion and healing such as the Celtic Goddess Brighid, or the Greek Goddess Eleos. Are we polytheistic or monotheistic? Both and neither. We feel the separate energy of the Gods and Goddesses so in that sense we are polytheists, but if we feel that all Gods are part or aspects of one God/Goddess we could be seen as monotheists. This is the beauty of Wicca, no one is going to tell you how to approach or relate to the Divine.
For people who identify as transgender, or non-binary the idea that God is only male, or only male and female, seems to upset them. But no matter how you feel about it, God/dess is the creator and fertility and procreation on earth are related to the interaction of male and female. That is nature. Wicca is a nature based or earth based spirituality, meaning that we feel the Divine presence in the Sacred Earth and the polarity of gender is part of that. So yes, for Wiccans, God is feminine and masculine; but wait...there's more!
This is how we approach but it is not the end of the story. As we develop our deeper mystic relationship with the divine we begin to see the Sacred within everything. The earth is sacred, so is the mountain, the rain, the wolf, the human being and love itself. You are sacred and you are also a manifestation of the Creator. Sacred is not gender specific or even species specific; the divine can manifest in any way that it wants because God is a spirit and how spirit manifests into the physical is part of the mystery of life.
In Celtic Wicca we might call in the Sacred energies of Anu the Great Mother paired with Cernnunos the Lord of Wild Nature but as they combine within the Circle their energy is more than the sum of both of them. It is a balance of Earth and Sky, masculine and feminine, above and below, intertwined in a magickal dance that becomes Spirit which transcends male/female and the concept of gender. Spirit just is! It is the source of life and the place life returns when it has finished the dance.
It's hard to approach this source energy, or develop a personal loving relationship with it, especially for people muddling their way to enlightened evolution like us. It's easier to wrap our arms around a tree and feel the pulse of the green heart of nature, equating that with the archetype 'Mother' or the protection of 'Father'. Gender is only a possible beginning place for our relationship with God and Wicca is a spiritual system that can guide you through the mysteries towards a deeper meaning of the Divine within and without. Don't get hung up on the words used to describe a profound non-verbal experience. Who or what is God? That quest is your adventure, an experience that is neither gender specific nor religion limited!