The death of Homelander in the comics was the result of a carefully orchestrated plan by a coalition of his adversaries. Each played a crucial role in bringing him down.
In the comics, it's a complex situation. Different storylines might have different outcomes, but as of the common ones, no one has directly killed Homelander.
I'm not entirely sure as I haven't read the 'homelander graphic novel' specifically, but typically in such novels, there would be a protagonist who is likely to be the homelander himself. There might also be supporting characters like his allies or those who oppose him.
Wu Zhu was considered one of the grandmasters at the peak of martial arts and possessed powerful sword techniques. The Shadow was Chen Pingping's personal guard. Although he had been taught by Wu Zhu, his strength was not as good as Wu Zhu's. Thus, according to the information provided, the shadow was unable to defeat Wu Zhu. In addition, the Qing Emperor was described in " Celebrating Years " as the pinnacle of human combat power. He possessed top-notch mental strategies and martial arts. The Qing Emperor practiced Tyrannical zhenqi, which contained a lot of zhenqi. However, other than zhenqi, the Qing Emperor was not much different from ordinary people. Although there was no clear mention of whether the Qing Emperor could defeat Wu Zhu, according to the information provided, Wu Zhu's strength was considered invincible, so it could be inferred that Wu Zhu could not be defeated.
Emperor Qing defeated Wuzhu in "Celebrating Years." Although Wu Zhu had powerful strength and special abilities, the Qing Emperor was the true leader of the Four Great Grandmasters. His King Path Fist and Tyrannical zhenqi were both very powerful. In their battle, the Qing Emperor won by a narrow margin and defeated Wu Zhu. In addition, Fan Xian also participated in the final battle. In the end, the Qing Emperor was secretly killed by Fan Ruoruo. Thus, the Qing Emperor was the only person who had defeated Wu Zhu in " Celebrating Years."