  In this paper we consider semileptonic lepton flavor violating operators of
the type $q^2l^2$ in low energy effective theory (LEFT). At the chiral scale,
we match these operators to chiral perturbation theory ($\chi$PT) and place
constraints from the process $\pi^0\rightarrow \mu^+ \,\, e^-$. These bounds
are shown to depend on the chiral nature of the operators. The scalar operators
are significantly more constrained compared to the vector operators. We then
compare the limits from $\mu \to e$ conversion in Nuclei and show that the
limits on scalar operators are within an order of magnitude of the
corresponding limits from $\mu \to e$ conversion in Ti. On the other hand, the
limits on vector operators are however much weaker. Towards the end, we evolve
the LEFT operators to W-boson mass scale using RGE, and match them to the
Standard Model effective field theory (SMEFT) operators. We, then, derive the
constraints on the parameter space of Leptoquark models that could generate
these SMEFT operators at tree level.
