In The Wind Waker, Medli is the sage of earth.
Medli is a young Rito from Dragon Roost Island who serves the dragon Valoo and cares for Prince Komali. During Link’s journey, she learns that she has inherited the sacred role of Earth Sage. Her ancestor Laruto, a Zora and the previous Earth Sage, appears to her and teaches her the Earth God’s Lyric, the song needed to awaken her power.
Medli accompanies Link through the Earth Temple, where her abilities help solve puzzles and reach otherwise inaccessible areas. Her prayers help restore the Master Sword’s power, which had weakened after the sword’s former sages were killed by Ganon’s forces. This makes her role important to both the dungeon and the game’s larger struggle against Ganon.
Laruto is the most common answer mix-up because she was the earlier Earth Sage. Makar is also a sage, but he is the Wind Sage and a Korok. Medli’s identity as a Rito reflects The Wind Waker’s setting centuries after Hyrule was submerged and its peoples changed over time.