Here is a picture of my test setup. No advancement so far with two F9P’s. I have checked configurations, all looks good. One of the modules has a blinking ‘no RTK’ so I guess communication between them is OK.
The pin numbers of ESPduino should be the same for ESP-32 dev kit? In the code, the TX, RX 1 and 2 are declared in the beginning, so should be fine I guess.