The class of Janus two-dimensional (2D) transition metal dichalcogenides with two different interfaces is interesting due to the possibility to access properties different from the typical 2D materials.  This dataset contains Quantum Espresso input files necessary to reproduce the density functional theory calculations within the associated publication. We used them to study the structural stability of 29 distinct ReX_{2-x}Y_{x} (X,Y=S,Se) structures, which can be obtained by selective exchange of exposed chalcogens in a ReX2 monolayer as well as to examine the lattice properties and electronic properties of the most stable Janus monolayers for given chalcogen composition. Additional information on the computational details of our work can be found in the Methods section of the published paper and the Supplemental Material linked to it.