Can hocd change sexual orientation? Can sexual orientation change due to hocd (Homosexual OCD). And if it can change, is it possible to reverse the change and bring the person back to his/her original orientation.
[Change from heterosexual to homosexual]
First of all, it is important to note that the current version (5th Edition) of the DSM — Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychological Association (APA, 2013) — does not recognise homosexual obsessive-compulsive disorder (HOCD) as a mental health condition (Smith, 2021).

Homosexual obsessive-compulsive disorder (HOCD) is a type of sexual orientation-obsessive-compulsive disorder (SO-OCD). A person with SO-OCD may have fears and anxieties relating to their sexual orientation.
[...]
A person with HOCD may have anxiety about experiencing same-sex attraction, even if they do not experience this.
Because HOCD is a type of SO-OCD, some people may use the term to refer to situations wherein people who are not heterosexual experience fears about their sexual orientation.

Reading this article will explain in more detail what HOCD is reportedly all about.
Can sexual orientation change due to HOCD?
The overarching point to put across regarding any sexual orientation is that nothing and nobody can make you homosexual, bisexual or heterosexual. There have been groups of therapists who tout that they can convert homosexuals into heterosexuals through conversion therapy, but:

conversion therapy in relation to gender identity and sexual orientation (including asexuality) is unethical, potentially harmful and is not supported by evidence (BACP, 2017).

For research on this, among many others there is:

Drescher, J., Schwartz, A., Casoy, F., McIntosh, C. A., Hurley, B., Ashley, K., ... &amp; Tompkins, D. A. (2016). The growing regulation of conversion therapy. Journal of Medical Regulation, 102(2), 7-12. https://doi.org/10.30770/2572-1852-102.2.7


Assessments of the peer-reviewed literature from multiple professional organizations, including the American Psychiatric Association, the American Psychological Association, and the American Academy of Child and Adolescent Psychiatrists, have found no evidence that conversion therapy treatments result in changes in sexual orientation.


Haldeman, D. C. (1994). The practice and ethics of sexual orientation conversion therapy. Journal of Consulting and Clinical Psychology, 62(2), 221–227. https://doi.org/10.1037/0022-006X.62.2.221


The literature in psychotherapeutic and religious conversion therapies is reviewed, showing no evidence indicating that such treatments are effective in their intended purpose


Adelson, S. L., &amp; of Child, T. A. A. (2012). Practice parameter on gay, lesbian, or bisexual sexual orientation, gender nonconformity, and gender discordance in children and adolescents. Journal of the American academy of child &amp; adolescent psychiatry, 51(9), 957-974. https://doi.org/10.1016/j.jaac.2012.07.004


Principle 6
Clinicians should be aware that there is no evidence that sexual orientation can be altered through therapy, and that attempts to do so may be harmful.

This led to the Coalition Against Conversion Therapy (CACT), a coalition of leading psychological, psychotherapeutic, and counselling organisations committed to ending conversion therapy, who prepared a Memorandum of Understanding (MoU) on Conversion Therapy in the UK (UKCP, 2017), and signed by many UK professional governing bodies, including (see the corresponding links) the National Counselling Society (NCS), British Association for Counselling and Psychotherapy (BACP), National Health Service (NHS), The British Psychological Society (BPS), and the Royal College of General Practitioners (RCGP).
References
APA. (2013). Diagnostic and statistical manual of mental disorders (DSM-5®). American Psychiatric Pub. https://www.psychiatry.org/psychiatrists/practice/dsm
BACP. (2017). Memorandum of understanding on conversion therapy in the UK https://www.bacp.co.uk/events-and-resources/ethics-and-standards/mou/
Smith, A. (2021). What is homosexual obsessive-compulsive disorder (HOCD)? Medical News Today https://www.medicalnewstoday.com/articles/hocd
UKCP (2017) Conversion Therapy https://www.psychotherapy.org.uk/policy-and-research/public-policy/conversion-therapy/