Gradient set for gradient maps!
Personally I like to use gradient maps on overlay over the original drawing, but it's possible to use them to color your drawing after figuring out suitable values.
It's possible to adjust the color range if they don't fit your values.
For that go to "Edit"-> "Tonal correction"-> "Gradient map" and choose the gradient set you want. You should be able to move around the colors to better match your illustration.
To add your downloaded gradient set, click on the wrench (tool) next to the gradient set bar. Click on the option "Add gradient set".
You are all set!
For this example I used gradient "Luminous"on overlay and added linear burn 20%.


Re-upload