Gender and sexuality are both spectrums. People are diverse.
People do get confused between sexuality and gender. I recently visited my parents and came out to them as transgender. I called a couple of days later, and my mother was worried about me not having a sex life all these years, as I am married to a woman. She didn’t initially understand that my gender has no relation to my sexuality. I was faking it as a cis hetrosexual male, when I was a transfeminine wannabe lesbian. Personally I like women, and love my wife.
Cis and trans people can be asexual or aromantic. I have colleagues at work who fall into that category, who I have met through the company LGBT group.
However sexuality can alter when people transition. Testosterone increases libido. Oestrogen reduces libido, so could make someone asexual. Oestrogen can also effect sexuality, making someone prefer male company.