  Context. Stellar internal magnetic fields have recently been shown to leave a
detectable signature on period spacing patterns of gravity modes.
  Aims. We investigate the effect of the obliquity of a mixed (poloidal and
toroidal) dipolar internal fossil magnetic field with respect to the rotation
axis on the frequency of gravity modes in rapidly rotating stars.
  Methods. We use the traditional approximation of rotation to compute
non-magnetic modes, and a perturbative treatment of the magnetic field to
compute the corresponding frequency shifts. We apply the new formalism to HD
43317, a magnetic, rapidly rotating, slowly pulsating B-type star, whose field
has an obliquity angle of about 80{\deg}.
  Results. We find that frequency shifts induced by the magnetic field on
high-radial-order gravity modes are larger with increasing obliquity angle,
when the magnetic axis is closer to the equatorial region, where these modes
are trapped. The maximum value is reached for an obliquity angle of 90{\deg}.
This trend is observed for all mode geometries.
  Conclusions. Our results predict that the signature of an internal oblique
dipolar magnetic field is detectable using asteroseismology of gravity modes.
