No, FlySky transmitters generally cannot be paired with receivers from other brands like FrSky. Each manufacturer uses their own proprietary communication protocols. For example, FlySky uses protocols like AFHDS, AFHDS 2A, and AFHDS 3, while other manufacturers use different protocols. As stated in one of the search results, "FrSky and Flysky are two completely different companies using two different protocols. You need to get a Flysky receiver" to work with a FlySky transmitter. However, some Turnigy and Eachine receivers may be compatible if they use the same protocols as FlySky.