Ye Luoli: Silver Tides

(Canon couples are split up, so don’t read if you dislike that. Original female protagonist x Water Prince.) Yin Xi is from another world. Carrying a System, she transmigrates into the world of Ye Luoli thousands of years in the past. At first, all she wants is to get home, but she unexpectedly becomes a legend in the fairy realm and even manages to capture the heart of a certain famously aloof prince, cool as water.

Shui Qingli: ...

(There are a great many original elements, and this differs considerably from the original plot. There may also be hostility toward the main cast, so don’t read if that bothers you.)