The Church of Jesus Christ of Latter-day Saints has a very clear stance on the topic of gender.
27 So God created man in his own image, in the image of God created he
him; male and female created he them. (Gen 1:27)
There are only two genders: MALE and FEMALE, every spirit child of our Father in Heaven (every human being ever born on Earth) is one of these genders, has been one of these genders since before the creation of the Earth, and will remain the same gender for all of eternity.
ALL HUMAN BEINGS—male and female—are created in the image of God. Each
is a beloved spirit son or daughter of heavenly parents, and, as such,
each has a divine nature and destiny. Gender is an essential
characteristic of individual premortal, mortal, and eternal identity
and purpose. (The Family: A proclomation to the World)
This stance was recently reaffirmed at the October 2018 General Conference of the Church:
...some are troubled by some of our Church’s positions on marriage and
children. Our knowledge of God’s revealed plan of salvation requires
us to oppose current social and legal pressures to retreat from
traditional marriage and to make changes that confuse or alter gender
or homogenize the differences between men and women. We know that the
relationships, identities, and functions of men and women are
essential to accomplish God’s great plan. (Truth and the Plan. 2018)
Gender is eternal and unchangeable. When our spirits were created an eternity ago, before the very foundations of the universe were formed, we were created as either male, or female, and we will remain the same gender throughout all time and eternity.