Confirmed working with
Install Python (Windows install link) and required dependencies using
pip3 install pyserial intelhex.
Download flashing tool from: https://github.com/JelmerT/cc2538-bsl/tree/feature/ITead_Sonoff_Zigbee-delay
Download Z-Stack firmware and place it in the same folder as cc2538-bsl
Run (change port accordingly):
python.exe cc2538-bsl.py -p COM4 -evw CC1352P2_CC2652P_launchpad_coordinator_20210708.hex --bootloader-sonoff-usb
Sonoff Dongle Plus is using CP210x, if you don’t have one, download the device driver from https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers