Digging a bit deeper, it looks like the library you’re using should handle the SoftwareSerial declaration and setup itself in the background, so the SoftwareSerial library probably doesnt need to be included, although its difficult to say without knowing exactly which library you’re using.
There is a known bug with the recent versions of the ESP core which affects SoftwareSerial…
Even if your PZEM library doesn’t require the SoftwareSerial.h library to be included, it’s probably using the library in the background so could be affected by this issue.
There’s also an issue with voltages on the latest version of the PZEM whne using it with an ESP. See this topic:
It would also help if you posted actual code and copy/pasted compiler error messages rather than screenshots. If you do this, ensure that you surround your code and compiler messages with triple backticks so that it displays correctly. Triple backticks look like this:
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Having said that, this isn’t a Blynk related problem at this point, as you’re not using Blynk in your sketch, so this probably isn’t the best forum to be asking these questions.