  We clarify novel forms of scaling functions of conductance, critical
conductance distribution and localization length in a disorder-driven quantum
phase transition between band insulator and Weyl semimetal phases. Quantum
criticality of the phase transition is controlled by a clean-limit fixed point
with spatially anisotropic scale invariance. We argue that the anisotropic
scale invariance is reflected on unconventional scaling function forms in the
quantum phase transition. We verify the proposed scaling function forms in
terms of transfer-matrix calculations of conductance and localization length in
a tight-binding model.
