1) Is it correct to represent the ESP-IDF error code as OSError code?
For example, for the code

from esp32 import RMT  
from machine import Pin  
rmt = RMT(1000, pin=Pin(10)) # 1000 is wrong  

we get an output

OSError: (-258, 'ESP_ERR_INVALID_ARG')

But I expect to see

EspError: (258, '0x102 ESP_ERR_INVALID_ARG')

(or something similar) according to errors

#define ESP_ERR_INVALID_ARG         0x102   /*!< Invalid argument */

from the
esp_err.h#L31

2) Is this line of code correct? Do you need a '-' here?

uint32_t pcode = -code;

from the
mphalport.c#61

3) Is it possible to develop a C module with esp_err.py functionality?
esp_err.zip

I try but it doesn't work completely.
mod_esp_err.zip
I get TypeError when executing esp_err_test.py

  File "<stdin>", line 9, in <module>
TypeError: can't create 'EspError' instances