You will most likely going to need to have the General EU A/T ECU, Toyota part # 89661-14530 if your car is general Euro Spec Auto Supra.
There might be some issues if using Austria / Switzerland A/T ECU, Toyota part # 89661-14550, as the Austria / Switzerland A/T ECU is programmed for different part # auto transmission and differential. But it also could work as it should.
Theres also a possibility to use USDM A/T ECU Toyota part # 89661-14510 / 89661-14511 as the engine wire harness is same between US/EU Supras, but US Supra ECU`s does not have as good ignition timing and fuel charts as EU ones do. Also the differential and auto trans are different from the Euro Spec Supra.