In this study, we explore the possibility of using a `dijet + dilepton + Missing Transverse Energy' (MET) signature to measure the neutrino Yukawa couplings in the Next-to-Minimal Supersymmetric Standard Model with right-handed neutrinos (NMSSM) when the lightest Supersymmetric partner (a right-handed sneutrino) is the Dark Matter (DM) candidate. We demonstrate that, unlike the minimal realization of Supersymmetry (MSSM) in which the DM candidate is a much heavier neutralino, the NMSSM model allows for a much lighter sneutrino to be the DM candidate, which can be produced at future $e^+e^-$ colliders with energies up to around 500 GeV. The resulting signal from chargino pair production and subsequent decay is very pure, providing the potential to extract the Yukawa parameters of the (s)neutrino sector. These findings may motivate searches for light DM signals at such accelerators, where the mass of DM candidate is around the Electro-Weak (EW) scale.