There is evidence that it is harder to sustain meaningful sexual relationships after medical transition.
A study  on informed consent found that male-to-female transitioners who are attracted to men may discover that men who are sexually interested in them are specifically interested in their trans status, and have no interest in serious long-term relationships.
The same study noted that male-to-female transitioners who are attracted to women may find that lesbians are unwilling to engage in a sexual relationship with a male.
Because most female-to-male transitioners do not undergo phalloplasty, their ability to attract desirable sexual partners, and sustain relationships with them, could be compromised.
Only a single case  of a female-to-male transitioner treated with puberty blockers followed by cross-sex hormones and surgeries has feen followed long-term.
The individual, who was in his thirties during the follow up, reported an inability to have a satisfying sexual life due to “shame about his genital appearance and his feelings of inadequacy in sexual matters”. The researchers concluded, that despite the gender reassignment, “in the area of intimate relationships, it may remain difficult to find a suitable partner”.
 Levine, S. (2018). Informed Consent for Transgendered Patients. Journal Of Sex & Marital Therapy, 45(3), 218-229. [Link]
 Cohen-Kettenis, P., Schagen, S., Steensma, T., de Vries, A., & Delemarre-van de Waal, H. (2011). Puberty Suppression in a Gender-Dysphoric Adolescent: A 22-Year Follow-Up. Archives Of Sexual Behavior 40 (4): 843-847. [Link]