>>105522672The original meme was black and white and most of the derivative memes also stick to black-and-white, with colored versions being the minority.
In keeping to this, I try to stick to black-and-white when the resulting image is clearly identifiable (as in, you can tell who the vtuber is). I also consider this more "challenging" and thus interesting.
But when the output might be ambiguous or generic without color, I use color. I agree the color is a bit more aesthetically pleasing in most cases, so I will probably "recolor" some of the black-and-white ones in the future to compare the difference.