  We studied the decays of Heavy baryon into a pseudoscalar meson and a dark
baryon in the recently developed $B$-Mesogenesis scenario, where the two types
of effective Lagrangians proposed by the scenario are both considered. The
decay amplitudes of $\Lambda_b^0$ are calculated by light-cone sum rules using
its light-cone distribution amplitudes. The decay amplitudes of $\Xi_b^{0,\pm}$
are related with those of $\Lambda_b^0$ through a flavor SU(3) analysis. The
uncertainties of threshold parameter and the Borel parameter are both
considered in the numerical calculation. The values of effective coupling
constants in the $B$-Mesogenesis are taken as their upper limits that obtained
from our previous study on the inclusive decay. The upper limits of the decay
branching fractions are presented as functions of the dark baryon mass.
