SysML tools can ALSO be used for many graphical Model-Based Engineering tasks that benefit from Single Source Of Truth - and even without any formal System Engineering methodology (which is NOT to say that formal System Engineering is not also useful).
Flow Port and Flow Specification are deprecated in this version of SysML and are defined for backward compatibility. Source OMG Systems Modeling Language (SysML) 1.7beta1
Webel: SysML/MBSE: Dr Darren's Open Letter on why you may initially need the Model-Based (MB) and Single Source Of Truth aspects of MBSE more than the formal Systems Engineering (SE) aspect (or even initially no formal SE process at all) to benefit most!
TIP: Mathematica: COMING SOON! Webel's ultimate guide to using Abstract Data Types to create pseudo-classes WITH INHERITANCE in Wolfram Language, all modelled in SysML! [There's already some examples and some detailed policy notes.]