It's a very good thing that we can now easily share colors between projects. But to be really useful, we need to change a linked color on a specific project.

I work on multiple projects based on the same UI library. Each projects has its own main color.

I created a project to maintain all my atomic elements and my other projects use those linked elements. But for now, when you use a linked color you can't change it on one project only so I can't use your great new feature for sharing assets between projects.

Here is how it could be implemented :
1. On the contextual menu of a linked color choose "Edit for this document"
2. Choose the new color
3. All the artboards and components with the first old color are updated with the new color

Complementary rule for linked assets updates : the unicity of a color is determine by its name and not its hexa code. So if a color has the same name in further projects, it has to be considered as the same color and not to be change by the update.