It's important that instead of making these changes as a kneejerk reaction that we understand why the setting should be changed for a digital artist, especially in this case because some people might use CSP for their physical prints they sell. Doing some quick reading on this, I came across this article that has a seemingly decent explanation of why the four options here do what they do. Also here is the explanation of this setting from Clip Studio Paint's website.
"Perceptual preserves the visual relationship between colors so that colors are perceived as natural even when color values are changed. Saturation compares the maximum highlight in the source color space with the maximum highlight in the destination color space, and shifts the difference. Relative Colorimetric tries to reproduce vivid colors, even at the expense of color accuracy. Absolute Colorimetric does not change colors that fall within the destination gamut, but changes out-of-gamut colors."
The article linked explaining the two options we are discussing (but also explains the other options on this drop down) :
- Perceptual - A perceptual rendering intent preserves the overall color appearance by changing all colors in the source space to fit the destination space. The perceptual rendering intent is favored for images that contain many out-of-gamut colors.
- Saturation - A Saturation rendering intent converts saturated colors in the source space to saturated colors in the destination space. It favors reproducing vibrant colors and will do so at the expense of reproducing hue or luminosity accurately. The saturation rendering intent is useful for reproducing graphics with high color impact.
TLDR, the options are to make it so that if you are to print the artwork to a physical copy, the colors are reproduced better and are still accurate to your art.
If you don't understand what color gamut is, its basically the colors that a printer is capable of reproducing and if you want accurate looking colors in print you need to consider how the piece is actually going to be reproduced by the printer.
Since your reference is something that you want the colors to be consistent on, you will want to change the setting as mentioned above. But if you are making a piece to actually print out then you might want to care more about this setting than just changing it and forgetting about it.