This firmware contains Ender 3, Ender 3 Pro, Ender 3Max, Ender 5Pro, Ender 2Pro.
We explain GD MCU as a replacement due to the global MCU supply issues.
We are afraid that there are some issues with other ender series products except above we mentioned, so it isn't recommended to use GD MCU firmware on other Ender series machines.
GD MCU firmware can be compatible with ST MCU firmware, but ST MCU firmware can't be compatible with GD MCU alone.