It’s probably not expanding uniformly in all directions. Gravity is different in different concentrations of mass, and mass is certainly not evenly distributed in the Universe.
I would think that the Universe is not a sphere but a lopsided blob that is expanding at different speeds in different directions..............
Could be , but the dimming of light from this magnification effect would still be true for any positive expansion starting from a point in space.
Maybe it only appears to expand in the direction that you're trying to measure - sort of the way a video game doesn't create the entire world but rather only the little bits that you can see as you move through and explore it.