The horoscope does not have to be all five elements. The important thing is that the horoscope should not conflict with each other. Earth is not important. Since water is the god of happiness, you should choose a name with water in it, or one with the radical "water".
Liu Zhaoqian "This is the homophony of the parents' surnames"
Liu Lu "just fits the meaning of being born in autumn"
Liu Yufei Liu Yuqian "these two are in line with fashion"
Each name brings help, and it also sounds refreshing!