The mission location of the copy of the Great Wall Watch is Li Yuecheng. Players need to destroy a certain number of enemies to trigger the challenge of "humiliating the memory of modern history" or "all the people are soldiers". During the mission, players need to successfully defend and destroy the emerging enemies in order to complete the mission objectives.
For more information about the replica of the Great Wall Watch, it is suggested to inquire or consult an experienced gamer in Genshin Impact Game official website.