Replace a variable when LoadState()

Hello experts!
I am using LoadState from paraview.simple to load a state file. We can readily provide a data directory there to replace the data in the file with a new one. Now I am also looking for a way to replace a specifically used variable the same way.
Lets say I have a dataset with two fields, one is called carbon.concentration, the other nitrogen.concentration. It is used in the state e.g. in a calculator function. I want to create the images in this state once for carbon (the state is build with this) and also for nitrogen. Is there a built-in search/replace mechanism that I can use to make this work?
The LoadState() function can take several arguments but I have not yet found a complete list anywhere, but I thought this is a possible approach.

There is not. You’ll need to use an external editing tool to do the find/replace.

Alright, I will find another way then.
Thanks for the swift clarification.