I've found en emulator that lets you colorize old GB games and have started on colorizing Mega Man V. For starters, I colored in Mega Man with his NES colors (and made it work on the GB, the sprites are slightly different), as well as a few enemies in Mercury's stage and Mercury himself.

I posted this topic on sprites, inc too, you can find that thread here.  Someone has already colored the Stardroids themselves, which is located here.

I was messing around with the idea of colorizing this game for awhile- an example of this would be a mockup I did several months ago:



Some sprites I've colorized since then:




The idea is to stay in the NES palette. The specific one I'm using is below:



It was stated that a lot of the ones I did looked bad because they used too many colors. I wasn't sure whether I wanted to break the NES limitations with that because all of the sprites are "shaded" in grayscale and look different from normal NES sprites because of that.

What I'm asking for here is if anyone wants to help out with this or just critique stuff I've already done / will do in the future.  Pixel work / art in general is not my forte so I am not sure how to color things from scratch.  Capcom has colors for a lot of these enemies and they are very strange, many are garish-looking or odd color combos.  Capcom's official screenshots from MMV when they were going to colorize it in Mega Man Mania also have a slapdash garish look to them so I want to avoid that. 

You can find the sprites here.  I will have to rip the backgrounds manually because I can't seem to find any background tiles ripped on any sites.