Here'a another take, where it takes the form of compact node.
I like this version more, because it means there could be a node for 'broadcast' and 'receive' (or 'listen') that makes it easier for new users to discover.
However, when attached, this becomes one of these compact nodes, which is neater. I'd propose making the compact Send/Receive show the right-click menu on regular click as well.
This functionality can also be made available on right-click of a port, where the user can select correctly-typed variables. This would be the faster way to access this functionality.
In the case this order of flow produces an error, then it would be nice for the UI to prompt to insert Spin Off node. Or at least offer that helpful tip.