hello what is male shirt that only 0000geom?

Hi. Tops for feminine frame come with extra bones (chest), so it is not advised to use them as a reference.
You do not need to subdivide anything for any purpose. All you need to do is choose Nearest face interpolated instead of the default option.


You should clone a base game tank top or a t-shirt, they are made of one meshgroup

With the default settings each vertex of your item gets the data from the closest vertex of the reference. When it comes to weights, the difference is insignificant unless your item is very high poly, which is something it should never be.
This is what it looks like on a low poly mesh, not a big deal

And this is what it looks like on a high poly mesh

To deal with it, the author increases the density of the mesh so that there are more vertices to get that data from. But an easier and better solution is to just change the settings, so that the data is taken from faces instead of vertices.
As for uv_1, unless you are transferring data to a topologically identical mesh, the result will not be good. So you should choose Nearest face interpolated no mater what.
Feminine and masculine frames differ in the shoulder and neck area, so i do not advice you to do that. Transfer them from the nude body