Have you considered broaching more in-depth conversations about the gender spectrum?
The notion that there is more to the world than a gender binary can spark very intriguing conversations between friends and partners (both short and long-term partners).
Obviously, approach the discussions and coming out with a healthy dose of caution. We all desire to be genuine and are comfortable in different ways.
My personal experience when coming out to my wife was that I prefer wearing women’s cloths and undergarments because they make me feel comfortable in my skin. At the end of the day they’re just clothes. When approached from that point of view it helped.
Hugs and care,