It might not be possible to determine the data flow between model blocks without simulating (or updating) the model. This is because if an error occurs in any referenced model, then the data won't flow from that specific block, which in turn prevents it from flowing to other blocks.
However, you can select Alias Data Types under Information Overlays to identify the data type being passed in the connection signals.
Moreover, what we can do is update the reference models causing errors. You can either replace those models with a mock model that has the same input and output data type or use conditional execution with the help of Enabled Subsystems or Triggered Subsystems. These can be activated based on certain conditions to prevent the error-prone logic from executing.
You can refer the following MathWorks documentation for more information:
