Xuan Ye recognized Ying Yuan as his son through the information that Ying Yuan had encountered a powerful enemy and revealed the shura mark that had been erased by the Venerable Sovereign, as well as Ran Qing's personal admission that she was pregnant and told Xuan Ye that they had a child. Therefore, Xuan Ye recognized his son through these clues and information.

Xuan Ye recognized that his son was real. There were many documents that showed that Xuan Ye finally recognized Ying Yuan as his son. In << Agarwood Fragments >>, Ying Yuan encountered a powerful enemy and revealed the shura mark that was erased by the Venerable Sovereign. This allowed Xuan Ye to recognize his son. In addition, there were also documents that mentioned that Ran Qing admitted to being pregnant and told Xuan Ye that they had a child. Therefore, based on the information provided, it could be confirmed that Xuan Ye had recognized his son.
Xuan Ye had found out about his son Ying Yuan through Ran Qing. In the plot of " Aquilaria Fragments ", Ran Qing told Xuan Ye that she had given birth to a son for Xuan Ye during the final battle. His name was Ying Yuan. Only then did Xuan Ye realize that he already had a descendant.
In the end, Xuan Ye recognized Ying Yuan as his son through Ying Yuan's encounter with a powerful enemy and the shura mark that was erased by the Venerable Sovereign, as well as Ran Qing's confession that she was pregnant and told Xuan Ye that they had a child. Therefore, Xuan Ye recognized his son through these clues and information.
Xuan Ye had learned that he had a son, Ying Yuan, through Ran Qing's narration. In the plot of " Agarwood Fragments ", Ran Qing told Xuan Ye that she had given birth to a son for him during the final battle. His name was Ying Yuan. At this moment, Xuan Ye realized that he already had a descendant. Therefore, Xuan Ye recognized his son through Ran Qing's narration.
Xuan Ye had learned that he had a son, Ying Yuan, through Ran Qing's narration. In the plot of " Agarwood Fragments ", Ran Qing told Xuan Ye that she had given birth to a son for him during the final battle. His name was Ying Yuan. At this moment, Xuan Ye realized that he already had a descendant. Therefore, Xuan Ye recognized his son through Ran Qing's narration.
Xuan Ye had learned that he had a son, Ying Yuan, through Ran Qing's narration. In the plot of " Agarwood Fragments ", Ran Qing told Xuan Ye that she had given birth to a son for him during the final battle. His name was Ying Yuan. At this moment, Xuan Ye realized that he already had a descendant.
Xuan Ye finally recognized his son, Ying Yuan. In the search results, there were several articles that clearly stated that Xuan Ye recognized Ying Yuan as his son. One of the articles mentioned that when Ying Yuan encountered a powerful enemy, he revealed the shura mark that had been erased by the Venerable Sovereign. This allowed Xuan Ye to recognize his son. Another article also mentioned that Xuan Ye knew that Ying Yuan was his son and planned to use him to revive Ran Qing. Although there were some articles in the search results that said that Xuan Ye did not know that Ying Yuan was his son, Xuan Ye finally recognized Ying Yuan as his son.
The son of the Worldly Sword Master, Ye Xuan, was Ye Guan. In the plot, Ye Guan became the guardian of the Guanxuan Universe and inherited the mission of his father, Ye Xuan. Ye Guan opened a new chapter and became the next Guardian of the Mysterious Universe.
Xuan Ye and Ying Yuan had indeed given birth to a child. In the plot of " Agarwood Fragments," Ran Qing handed over her newborn child to the Overlord before she perished with Xuan Ye in order to protect the world. However, more details about the child's development were not explicitly mentioned in the information provided. Therefore, regarding the specific situation of Xuan Ye and Ying Yuan giving birth, we are unable to get a definite answer from the search results provided.
There was no specific time when Qing 'Er recognized Ye Xuan as her brother in One Sword Dominance. In her previous life, Qing `er didn't immediately recognize Ye Xuan as her brother. It was only during a crisis that Ye Xuan saw Qing` er's eyes and recognized his younger sister. Therefore, the specific time of recognition was not given in the information provided.