UML Port conjugation is dead (in SysML-1.6); Long live conjugation of the Port's type!
Since SysML-1.6 use of direct UML conjugation of Ports is NOT supported; If you are using InterfaceBlocks use instead a conjugated ~InterfaceBlock type!
The mechanism for conjugated Ports has been changed in SysML 1.6, it now conjugates the Type! If you are using an InterfaceBlock to type a Port you can conjugate that 'original' on another Port by typing it with an ~InterfaceBlock.
SysML-1.6: 'The ~InterfaceBlock stereotype (shall be pronounced: "conjugated interface block") is a specialization of InterfaceBlock that has the same features as its original InterfaceBlock except that its DirectedFeatures and FlowProperties are reversed (conjugated'
SysML-1.6: 'InterfaceBlock ... for example, in flow properties are conjugated as out flow properties and provided features are conjugated as required features. '
SysML-1.6: 'Conjugation is specified by a constraint giving the features of ~InterfaceBlocks according to those of their original InterfaceBlocks ... It is expected that tools conforming to this specification automatically create features of ~InterfaceBlocks.'Unfortunately: