You would use this expression for controlling different color options. This example below is based on two color options. You can have as many as you like.
Components that can have their color changed include: accent lines, text, text backgrounds, scene backgrounds, shapes, etc.
1. First make a new composition naming it DESIGN_CONTROL, labeling it none.
2. Bring the DESIGN_CONTROL into the MAIN_COMP - making sure it is labeled none in the MAIN_COMP and in the footage panel. Once the DESIGN_CONTROL is in the MAIN_COMP make the sure the visibility on the layer is off.
3. Inside of the DESIGN_CONTROL comp, make two adjustment layers. Rename the layers according to your desired color options. Then label them dark green.
4. Then go to effects and presets - searching for color control. Apply the effect to both adjustment layers.
5. Go back to the main comp - apply the effect fill to a layer you wish to control the color of. Alt clicking the stop watch of the fill effect color an apply this expression: comp("DESIGN_CONTROL").layer("layer name in design control").effect("Color Control")("Color");
6. Once you have applied the expression to each layer you desire to control you can go into the DESIGN_CONTROL and change the colors. This setup allows our system to read the dark green adjustment layers via a spreadsheet.