(Help) Changing digital-to-analog sensitivity on the fly?

[CitricDolphin]

I'm trying to play an N64 game that requires me to press the analog stick lightly, but I'm using a physical d-pad as my analog stick input. No, I will not use a different controller.

What I want to do is have a hotkey on my physical controller (e.g. R1) that will cause the emulated analog input to be lowered. For example, normally the stick will move to 100% range when I press the d-pad, but with the hotkey held, it would only move to 20% or something like that. Dolphin (standalone) has a feature like this but I can't find anything like it in Retroarch.

Is this possible?