Replacing a color in 3 simple steps: (1) Select source color (2) Pick target color (3) Apply to selection or entire edit context
Additional greyscale mode
If you have assets from different source with too many colors greyscale mode is perfect. Great for scribbles and wireframes. Or get rid of all color related emotions and focus on the user journey only.
Additional tint mode
Tinting means converting all colors to shades of one single color. Great for reusing templates with different color schemes.