B-meson decays occurring through $b \to s$ transitions are excellent probes for new physics, as
they are forbidden at tree level in the Standard Model. Thus, new physics contributions could
be unequivocally identified from any deviation from their predicted branching fractions. Recent
results from studies of these decays at the Belle II experiment are reported here. These results
are based on a dataset corresponding to an integrated luminosity of 189 fb$^{−1}$ and consist of
measurements of $B \to K^* \ell^+ \ell^-$, $B \to J/\psi(\ell^+\ell^-)K$ and $B \to X_s \gamma$.