I am thinking of sanding the anno ( I think this is what you would call it. I don’t know much about anno or finnishes) off of my Lunatic. Now, would I connect the axle to a drill with the yoyo still attatched, and sand like that? Would this even work well? Thanks. 
When I did the rims of my DV888 I did it by hand, it doesn’t take too long, just start of with start off with some 200 or 400 grit emery paper then gradually use smoother emery until you get the finish you desire.
Now, would this affect play at all?
If you don’t do it perfectly, you may end up with a vibe.
not really all you are doing is removing the anno coating, I suspose that if you where to do it with a drill there would be more of a chance you would affect the play, but doing it by hand is much more controlled and less likely to cause a chage to the play.
Okay so if I do it by hand then it will be more even?
Doing it by hand will make it less even.
Im just saying that with a drill it may be possible to take away the material faster ,thus posibily introducing an uneven weight distribution. This is all just a guess on my part because I havent used a drill to sand down a yoyo yet.
Using a drill or lathe will cause the material to be removed more evenly than any other method.
All that an annodized finish is, besides color, is protection. When aluminum is annodized it makes it 50% stronger on the outside, protecting the inside perfectly. So the whole idea of sanding that off dosnt make much sence because all ur doing is making your yoyo more in danger. Just my two cents
It won’t break