  We analyze theoretically the magnetic anisotropy in the nematic phase of FeSe
by computing the spin and the orbital susceptibilities from the microscopic
multiorbital model. In particular, we take into account both the $xz/yz$ and
the recently proposed non-local $xy$ nematic ordering and show that the latter
one could play a crucial role in reproducing the experimentally-measured
temperature dependence of the magnetic anisotropy. This provides a direct
fingerprint of the different nematic scenarios on the magnetic properties of
FeSe.
