The issue with those models is how there made, they would not animate well, and the rigs I use would not work right, already tried. How ever they can be remade, the same ones. Just done with quads instead.
So that shouldn't be an issue for you guys at all. They can be made the same size and everything thats not an issue what so ever. Skinning is not a big deal either. As far as animating, myself and the other person would have to know what would you like to know what poses, do you guys need, also how many frames do you need, want etc. Pretty much all that info will be needed.
As far as the models do you want new texture's or do you have some that your already wanting us to use? We would need to know this as well. This is some of the info, we would need .