You can completely remove the low voltage board and connect as shown below. GPIO0 needs to be pulled to ground on power up (it can be left grounded during flashing) to enter programming mode. Power the device from your FTDI programmer set to 3.3V . The Sonoff Touch is a nice glass touch panel based on an ESP 8285 with 1MB of integrated flash that can be quite easily flashed with a self compiled version of ESP Easy. You need to compile yourself as the builds available online are all made for the ESP8266 and will not work with the Sonoff Touch.
My collection of Home Assistant, CoreELEC, IoT, Synology, Kodi and other technical tips gathered over the years.