Use a simple ESP82xx device to connect to the vtrust-flash access point as required by Tuya-Convert. This simple sketch continually attempts to connect to vtrust-flash until successfully connected. This eliminates the need to connect a PC or a mobile device to this AP.
Use a NodeMCU or a Wemos D1 Mini and flash tc_donor_mini.generic_1M.bin on it using the usual Tasmota flash settings (DOUT, erase flash, etc.).
Once the device is flashed, apply power and start the Tuya-Convert process. As soon as the start_flash.sh script creates the vtrust-flash access point, this device will connect to it. The LED will blink until it connects (i.e., while disconnected) and then will remain lit solid when connected to vtrust-flash. This device will remain connected to vtrust-flash as long as the AP is available (throughtout flashing one or more Tuya devices). When you are done flashing your Tuya device(s), simply power off this device.