Two-dimensional MoS2 is a promising material for nanoelectronics and catalysis, but its potential is not fully exploited since proper control of its multiple phases (H, T, ZT) and electronic properties is lacking. In this theoretical study, alloying is proposed as a method to stabilize the MoS2 T-phase. In particular, MoS2 is alloyed with another material that is known to exist in a monolayer MX2 T-structure, and we show that the formation energy difference among phases decreases even for low impurity concentrations in MoS2, and a relationship between impurity concentration and alloy band gap is established. This method can be potentially applied to many two-dimensional materials to tune/enhance their electronic properties and stabilities in order to suit the desired application.