flipperzero-flasher-board
Since version 0.70.1 you can set RTS/DTR pins to pins 16/15 and use only one row of pins for this flasher board.
I made this simple board to flash my ESP32 projects. It uses the ESPFlash pinout. Flasher has a switch to toggle 3.3V from Flipper Zero if you need to power the device you are flashing from an external power source. Recommended PCB thickness is 1.0 - 1.2 mm.