Assuming you don't have any documentation for the tracking implementation (which should outline what is and isn't being tracked and where), you would still need to test the scenarios manually to find out.
Using a tool (browser extension) like the Experience Cloud Debugger or Experience Platform Debugger, you will need to manually go through all the flows (possibly in a QA or UAT environment, or maybe even on Prod if you are concerned about inconsistencies between environments).
If you are testing on a browser that doesn't have the extension available, then you can look at the Network panel in the developer console (filter for "b/ss") and look at the actual server call, you may need to copy it out to something where you can break it out to read it easier. Parameters like c2 are props (c being custom prop, 2 being your prop number), v5 are eVars (again the # corresponds to the eVar number), g is the backend URL, ch is your site section, etc). It's not as easy to test this way, but is doable.
Then you will have to read through all the collected data and see if emails are being collected and where.