You're welcome!
If you already need ESP32 for its communication and processing capabilities AND your ADC doesn't need that much resolution, you should be just fine staying with ESP32 ADC - all you need to do is increase the voltage divider ratio so that the range you need is included in the linear ...

ESP32 is well known for its ADC issues, including noise, incomplete range and NON-LINEARITY which you are asking about.
https://www.luisllamas.es/images/20164/esp32-adc-response.webp
If you can see the image above, you will see why you have the problem.
The ESP32 ADC has an internal voltage ...