This glitch allows you to use Farore's Wind anywhere. You cannot have won Epona off Ingo yet.
You can now use Farore's Wind anywhere. However, all C-items are disabled except for the Ocarina, and songs played on it won't do anything. Performing some actions, such as swimming or climbing a ladder, will disable the B button. To return the game state to normal simply return to Lon-Lon Ranch during the day.
This can also be done with Restricted Items to warp away instead of Bottle Adventure. First, set farore's wind in a dungeon or use Restricted Items to set it elsewhere. Next, have a Dimmed Blank B button and go to the Ranch before stealing epona. Pay for a minute of horse riding and once it starts make sure you have ocarina on a C-Button. Get on a horse, then equip Farore's Wind over the button ocarina was on. You should now be able to use that C-Button to warp away with Farore's Wind. This method does not allow Farore's Wind anywhere.
This glitch allows you to put bombchus and the fairy slingshot on B as a child.
Once the game ends you'll have the Slingshot/Bombchus on B. If you bring up the subscreens (pause) the B button will return to its normal state (Kokiri Sword).