She does! In Season 10, Dawn discovered she could express "god-like" powers in dimensions that were entirely magic-based, such as:

• sense possible portals;

• open portals to other dimensions;

• destroy barriers separating dimensions (which can lead to an apocalypse);

• shrink and destroy powerful demons;

• create force fields;

• and sense poison.

Spike then created a magic rule about the Key retaining her power to open portals even on Earth, and, in Season 12, Dawn used it to time travel and banish demons with the help of Willow and Illyria.

You can read more in the Dawn Summers article:

Dawn SummersBuffyverse Wiki