Get data from serial port

[Mahko_Mahko]

@breexly

if (sscanf(str.c_str(), "L%fM%f", &sensorL, &sensorM1) == 2){
            id(level).publish_state(sensorL);
            id(moisture).publish_state(sensorM1);
          }

I would use lots of little print/log statements to work through correct parsing of the values you want.
ESP_LOGD().

Custom Sensor Component

Also as Nick said, share logs as you go …

You might find some useful things here too:

[How to] UART read without custom component

The UART Bus component provides a write action but no read actions. Typically the UART read is implemented in a custom component that also does the processing. The UART debug sequence can be exploited to act like a call back function whenever there is received data to process. So basically instead of creating a small custom component a large lambda call can be used in the UART debug yaml. This is shared to hopefully help make implementing UART devices a bit easier for average users. It seems t…