  Identifying the existence of specific functional groups in MXenes is a
difficult topic that has perplexed researchers for a long time. We show in this
paper that in the case of magnetic MXenes, the magneto-transport properties of
the material provide an easy solution. One of the fascinating properties that
MXenes offer is the realization of intrinsic ferromagnetism which is important
for two-dimensional (2D) materials family. The previous reports have only made
a few statements on some MXenes citing its usefulness for spintronics related
applications. Here, using first-principle calculations we have examined the
actual magneto-transport phenomena in MXenes family. We have considered all
possible combinations of 3\textit{d} transition metals ($Ti, V, Cr$ and $Mn$)
and nitride based functionalized $(O_2, F_2$ and $(OH)_2$) MXenes, $M_2NT_2$.
The intrinsic anomalous Hall effect is investigated in $Cr$ and $Mn$ based
MXenes as the compounds possess ground state stable ferromagnetic solutions. We
demonstrate that intrinsic Anomalous Hall conductivity (AHC) can be used to
identify the functional groups in MXenes.
  Additionally, half-metallic features of these ferromagnetic MXenes make them
potential candidates for varieties of applications such as in logic and memory
devices, quantum computations, spintronics etc. The maximum anomalous Hall
conductivity (AHC) at Fermi energy, $E_F$, is found in case of $Mn_2NO_2$ (470
$S/cm$) which is attributed to the presence of avoided band crossing and larger
density of states. Together, when considered all the studied systems, the AHC
can be above 2500 $S/cm$ within $E_F \pm $ 0.25 $eV$. Our findings could be
useful not only in guiding the experimentalists by considering AHC as a simple
tool in determining the functional groups in 2D ferro(i)magnets, also, it could
be useful in designing memory device with negligible stray fields.
