Hi there!
The problem is being flagged here, on my Class Curve Plugin:
The alias is supposed to return a number, but it is returning undefined. So I try to track down most info I could, to understand why the alias is returning undefined.
Basically, the Game_Actor.prototype.param is that code below, by default, inherited from Game Battler Base:
So I assumed, some of this code above is returning undefined. So on the Game_Actor.prototype.param I tried to print all these values into the console to see their values. The result is below:
As you can see above, All values returned a valid number, just fine. Only the alias returned undefined. It means, that some other plugin is doing something with that function, that is causing the undefined. And it is specifically with the Parameter ID 6.
I removed the JS code from your state 36, and everything worked fine. I guess that your State Id 36 is doing something on your game, that is affecting whatever is inside the .prototype.param function, specifically with parameter ID 6.
I can't understand what it is. You have an enormous amount of plugin, and a lot of them is Visustella. I believe I could find a hint as to what is causing the problem, by tracking the start of it, which is on the last lines of the console error, VisuMZ plugins. Unfortunately, as you know, they have their code obfuscated, so there is no way I could understand what is happening there(the same way you did with my plugin) .
I tried to disable those plugins, but the error keeps showing other Visu plugins.
POSSIBLE SOLUTION
On my plugin, on line 1187, replace that line with the below:
const value = (alias ?? this.paramBase(paramId) + (this.paramBasePlus(paramId) * this.paramRate(paramId) * this.paramBuffRate(paramId)) ).clamp(minValue, maxValue)
That prevents the error from happening, but it can make something not work properly, I don't know what because I don't know the cause of the problem. That at least will prevent the error from happening.
CONCLUSION
Don't know what it is, and will not try to find the problem.
You should either discover why the parameter ID 6 is returning undefined. Don't know if State 36 is doing some work on another part of your game that is affecting this, if it does, then the problem could be much bigger to find out. Or could be a compatibility issue. Don't know.
You either try to reach them out to see if they can fix it, do not use the passive state the way you are doing with State 36, or remove my plugin.
Good luck!