Studying patients who had felt like women at all times for at least a year, Blanchard classified them according to whether they were attracted to men, women, both, or neither. He then compared these four groups regarding how many in each group reported a history of sexual arousal together with cross-dressing. 73% of the gynephilic, asexual, and bisexual groups said they did experience such feelings, but only 15% of the androphilic group did. He concluded that asexual, bisexual, and gynephilic transsexuals were motivated by erotic arousal to the thought or image of themself as a woman, and he coined the term autogynephilia to describe this.
The above is from Wikipedia. I know we can't trust it, but given its very TRA adjacent editing, this must surely be the best case scenario. 73% of non-homosexual transitioners that he studied, were erotic cross-dressers.