This pursuit of validation as "women" can be so strong that it leads some autogynephiles, who are actually straight men, to seek validation through having sex with men.

According to a reddit sub called r/Blanchardianism, this is called "meta-attraction".

Leaving aside why people who are not lesbians are posting on a subreddit called "Femme Lesbians" or at least do not have flair indicating that they are not lesbians but something else, I honestly feel bad for this poster. Of the people responding, their profiles reveal them to be bisexual women and one trans porn account soliciting views.

I am not someone who has anything against bisexual women or any qualms about having a bisexual partner, but what I do have qualms about is bisexual women speaking on behalf of lesbians and giving so-called transbians a false sense of how exclusive homosexual attraction works. This poster is visibly male and a lesbian is not just not going to be attracted to that, and that's not a reflection of the self-worth or humanity of the poster or of the values of lesbians.

I will also note that the poster's wording is interesting as they are exclusively focused on being attracted to "femme lesbians" and not femme women generally, which would include bisexual women. The implication, if this language was purposeful, is that they are more interested in being validated as a woman than finding a partner with mutual attraction. If these bisexual women want to be supportive and look out for the best interests of the poster, they should encourage the poster to expand their dating pool to include femme bisexual women.