Ok, so you want to create one legend and 'add' it to many linked projects?
(i.e. creating a Door Types Legend for a large multi-model project).
The best way to do this would be to create a legend, and then link the legend view into the other projects - but the Linked View feature doesn't work with Legends.
There is no way to do this efficiently in Revit. The existing Linked View feature should be extended to legends.
