Note that to play nicely with SysML flow properties your MUST use a SysML ItemFlow not a UML InformationFlow and the tools help enforce this.
A SysMLv1 ItemFlow without an assigned 'itemProperty' is sometimes informally/casually referred to as an "information flow", especially when applied to an Association (because they are much like a UML InformationFlow with just a 'conveyed' Classifier), but formally it is still a SysML ItemFlow.
SysML1.7: 'The itemProperty attribute has no values if the item flow is realized by an Association.'
In SysML1.7 the permitted Classifier types that may be 'conveyed' are restricted:
SysML1.7: 'ItemFlow::2_type_restricted An ItemFlow itemProperty shall be typed by a ValueType, Block, or Signal.'
Finally, note that while the UML InformationItem (which extends Classifier) is in the UML4SysML subset for SysMLv1, it is not explicitly used or otherwise referenced in the SysMLv1.7 spec.
If you are interested in some early SysMLv1 history and some of the dirty details visit this ARCHIVAL slide page (the please ignore it forever after and use a SysML ItemFlow):