Right-handed neutrinos νR play a crucial role in flavor-changing neutral-current processes with missing energy, such as and , where Belle-II reports unexpectedly large branching fraction in \( B\to K\nu \overline{\nu} \) decays. Assuming νR is the partner of the active neutrino νL in the standard model, a Dirac-type neutrino framework emerges. We investigate a scenario of radiative Dirac neutrino mass generation in a scalar leptoquark (LQ) model with a global U(1)X symmetry to suppress Majorana mass, tree-level Dirac mass, and diquark couplings. The simplest LQ realization consists of two S1 = (3, 1, −1/3) LQs with distinct U(1)X charges. A non-Casas-Ibarra parametrization is proposed to match neutrino data with fewer model parameters. Imposing current experimental constraints from meson mixing and lepton flavor-violating processes, we find that right-handed neutrino effects can significantly enhance \( B\to {K}^{\left(\ast \right)}\nu \overline{\nu} \) and \( {K}^{+}\to {\pi}^{+}\nu \overline{\nu} \) . Additionally, the model predicts excesses in RD from \( B\to D\tau \overline{\nu} \) that remain within 1σ of current experimental data.
