DataArea or DataPointer
By default, "DataArea (InputDst)" is selected as Input connection type at generated TwinCAT module. This means that a TC Module Input is created as Input Destination DataArea and a TC Module Output accordingly as Output Source DataArea.
Alternatively, "DataPointer" can also be selected here, see Shared memory between TcCOM instances.
If the Simulink® model shown above is created with the Target for Simulink®, 2 inputs and 2 outputs appear in the process image on the TcCOM instance if "mapping" is selected as Input connection type at generated TcCOM module.