If you think that modifying the Blynk library will give you more usable GPIOs on your ESP8266 then you are mistaken. Blynk simply works with the hardware that Espressif creates, and the limitations that I’ve pointed out to you in another topic are hardware rather than software related.
If you need more GPIOs then you either need to move to an ESP32 (the simpler option) or add an IO expansion board such as the MCP23017. This is a more complex and more expensive solution, but is documented here:
If you’re trying to achieve something different then I’d suggest you explain in more detail and we’ll try to point you in the right direction (but that almost certainly won’t involve hacking the Blynk libraries).
Pete.