As for other questions, is it true that you have to use specific colors or else it won't be GBA-friendly and won't work? If so, are these colors okay (as in, do they function at all):

(the last blue color is the background)
I don't mind if the colors stand out too much or anything; just wondering if they will work at all.
Is there any way to (easily) replace all pixels of a specific color with another specific color? One of the reasons why I don't like making portraits myself is because I squint at the screen and recolor every pixel manually on MSPaint. >_>
Does anyone have the enemy Mamkute battle sprites (like Yahn's) from FE6? I can't find them anywhere. Also can't find the FE7 enemy Mamkute battle sprites (or are they the same? I don't remember).