As long as you have defined the first sphere of center (x1, y1, z1) and radius r1=6371,
x = x1 + r1 * np.outer()
y = y1 + r1 * np.outer()
z = z1 + r1 * np.outer()
then the second sphere of center (x2, y2, z2) and radius r2 will be:
defined by:
x = x2 + r2 * np.outer()
y = y2 + r2 * np.outer()
z = z2 + r2 *np.outer()
The arguments for np.outer() are the same for both spheres.
Hence you have to set x2, y2, z2, and r2.
For the already plotted sphere, the center is (0,0,0).