It has been tested that GODIAG GT100 OBD2 Breakout Box and SVCI 2020 (VAG V21.0 software) can do Immo off on VAG EDC16U31 ECU.
The test:
This is the wiring diagram.
Connect GODIAG GT100 and VW ECU by the Godiag professional cable
Connect GT100 and SVCI by the Godiag OBD 2-in-1 extension cable
Keep voltage 12v+
Run SVCI software
Click VAG software>> V21.0>> Continue
Select Engine Control Unit to identify control unit information
Read DTCs and clear DTCs, then reset
Go to Special functions
Select Engine Control Unit>> EDC16U31
Read ConIData
Read data successfully
Then press Immo OFF
Follow the on-screen instruction to operate
Turn ignition OFF within 3 sec
Turn on ignition
Turn ignition OFF
Turn on ignition
Immo changed
Turn ignition OFF
Turn on ignition
Alright, EDC16U1 IMMO off job is done by GODIAG GT100 and SVCI 2020 ABRITES Commander.