I'm afraid it won't be possible to do exactly what you want. Ideally if you fit every EA for desired indicator.
Function for custom indicator used in the code is this:
https://docs.mql4.com/indicators/icustom
there is not much to be done there (due to the possibility of different types of input variables)
partial solution could be, left the Param. field empty and change the input parameters manually in an indicator code, but it's quite uncomfortable