Excuse me, about the extinction of Gundam mode.

Wateriness is good, because if your original paint is waterborne, it will be coated with oily matt paint. Because thinner of oily paint can dissolve water-based paint, on the contrary, thinner of water-based paint will not dissolve oily paint, so water-based matte paint will be safer.

Similarly, if your original paint is water-based, oily paint may be the original paint, but it is ok to be careful, because many people are oily paint now.

Don't choose wet weather, because it will prolong the drying time of paint.

It depends on what effect you need. Mainly by looking rather than touching. As shown in the figure below: