Sabrina Vitellia is an Imperial smith and owner of the local smith shop in Raven Rock. She only appears if having the smith shop built during the quest Setting up Shop. If the other is chosen, then the trader shop with Sathyn Andrano will appear instead.
The Nerevarine has been asked their opinion on whether a smith or a trader should be brought into the colony. They should ask the colonists what they think, then report their decision.