We study core-shell bimetallic nanoparticles using the first-principles approach to understand how the arrangement of the metallic domains affects their plasmonic features. Our research investigates changes in the position of plasmonic resonances, strength, distribution of the electromagnetic field, and generation of hot carriers. We design a nanoparticle with two separate plasmonic resonances and demonstrate that it can be strongly coupled with two distinct molecules. As a case of study, we chose Na/Mg nanoparticles in core-shell geometry and benzene derivatives as molecules.