Ganjiang Mo Xie: Five Tactics of Warring States Policy: "(Su Qin said that King Qi Min said) Although you are a Ganjiang Mo Xie, you can't cut it."
Longquan: The Spring and Autumn Annals of Wu Yue and other ancient books contain: Longquan sword "The turtle is full of rhyme, the dragon algae and rainbow waves are visible to the naked eye" /zhxx/lqtszj/lqbj/bjts/ This website introduces Longquan in detail.
Daya: In the story of the sword, the King of Chu invited General Ou Yezi and Mo Xie to Xiping Tangxi to cast Daya's famous sword, and replied to the King of Chu: "If you want to know Daya, look at its pattern, its wings are as high as flowing waves."
Fish intestines: Biography of wuyue and Liao Wang in the Spring and Autumn Period: "Make Zhuan Xu put the fish in the fish intestines sword." It means a small dagger that can be hidden in the belly of a fish. It is said that the arts and sciences of the sword bend like fish intestines. See "Huai Nan Zi Xiu Wu Xun": "The fish intestines are hooked from the beginning to the end, and the blows cannot be broken, and the thorns cannot enter." Refer to Song Shen Guo's Meng Qian's Writing on Chess.
Please refer to Baidu Encyclopedia for details.
Since there are written records, it is indeed possible for these famous swords to appear in history, but their specific power will be discounted. The ancients wanted to like exaggeration.