Changing Sprites and Palettes

Excellent, now, concerning FF3SE, I assume that if I tinker with the pixels of a given sprite without changing the palette, the sprites who share that palette will not be effected; is this the case?

It's the other way around. Let's say you have monster A and B sharing the Guard sprite. Changing palette on A will do nothing to B but changing a pixel on A will reflect on B but it might not be the same color change if the palette is different.

Edit: Sorry I think I've misread; changing a pixel does not affect another monster having different graphics but sharing the same palette.