Elfabelle is the Leader of the River Elves, a group that has been conflicting with the Tree Elves, led by Arielf, for a long time, as they do not like each other.
Her only appearance was in "The Elf Situation". There, it is revealed by Sofia and James that the reason for the feud is because Elfabelle broke Arielf's great grandelf's best family dish by accident, and Arielf broke Elfabelle's great grandelf's family dish to get even due to thinking she did it on purpose. They come up with an idea for Arielf and Elfabelle to have fun, but Amber shows up to air their grievances, but she eventually realizes her mistake and decides that the elves can have fun. It works, and the elves make peace.