Note: Learning the Earth God's Lyric before beating the Forsaken Fortress 2 will crash the game due to wrong animation sets. See here for more info.
It is posible to enter Headstone and learn the Earth God's Lyric without the Power Bracelets. This can be useful for routing purposes.
First, you will want to get on top of the east side of the island using either a bomb boost or a ledge grab out of the leaf. Once up there, go to the corner. In that corner, you can roll clip to go OoB and from there enter the loading zone using the leaf.
This also works on this other corner:
If you have chest storage, you can easily clip through the corner left of the headstone and leaf to the loading zone from there.
If you don't break the Headstone preventing you access to the Earth Temple, the cutscene of you and Medli entering Headstone together will softlock, due to Link not being able to reach the position in which the game is supposed to start the loading of the next area. This can be avoided by skipping the cutscene with Storage, or by superswimming to Headstone with Double Storage (same thing).