From the top answer to What does Islam say about homosexuality?, we have

The Sahaabah were unanimously agreed on the execution of homosexuals, but they differed as to how they were to be executed.

(although no reference was provided to support this claim). However, this is at odds with the following ahadith:

... Allah's Messenger (ﷺ) never killed anyone except in one of the following three situations: (1) A person who killed somebody unjustly, was killed (in Qisas,) (2) a married person who committed illegal sexual intercourse and (3) a man who fought against Allah and His Apostle and deserted Islam and became an apostate. ... -- Sahih al-Bukhari 6899 (sunnah.com)

... It is not permissible to shed the blood of a Muslim except in one of three cases: A man who reverts to Kufr after becoming Muslim, or commits adultery after being married, or one who kills a soul unlawfully. ... -- Sunan an-Nasa'i 4019 [grade: sahih] (sunnah.com)

They differ in that the first one lists who the Prophet killed, whereas the second one lists who the Prophet permitted killing. Nevertheless, both are sahih. However, there's an omission here... homosexuality.

Question: If homosexuality should result in execution, why is it not listed in ahadith as a reason to kill someone?

Given that homosexuality carries the death penalty in some Islamic countries*, I would expect there to be crystal clear evidence that the Prophet actually condoned this behavior.

^{* Washington Post, 2016, lists: Afghanistan, Iran, Mauritania, Nigeria, Qatar, Saudi Arabia, Somalia, Sudan, United Arab Emirates, Yemen}