Raw input mixed with stabilized input ? #4872
I suggest using the "servo autotrim" feature to trim your aircraft and then fly in "manual mode" for the raw steering experience. There is basically no need to trim manually in inav.
Alternatively you could set up some conditions in your radio with trims only active when the mode switch is in the position for "manual mode" in inav. And trims disabled or set to zero when the mode switch is set to RTH.