ability to save texture with custom size + interpolation method choice

For instance  I have a texture  512x4096   and want to save  it 512x2048  .   I have to go to Designer  or  Affinity Photo for that .  Adobe ,please make  it possible to save in whatever size  I want and add pixel interpolation options .  Like Lanczos3 non separable in Affinity photo.   The best pixel  interpolation  so fat for textures IMO  where I don't need to put extra sharpen node  that adds its own artifacts .