Automate with Safari Web App?

Hey I'm hoping someone may have an idea for this.

So basically my work using a project management app for collaboration, including planning our social media schedule. I'm currently then copy and pasting from this app into our social media scheduler (in a Chrome page).

I thought it'd be clever to create a Safari Web App instead of using the official app so I could create automation to pull from fields in the project app and paste into the social media app to make things quicker and avoid mistakes—so I could still use it as an app but I assumed I could also use KM to identify the fields because it's still Safari underneath.

I also found this guide to getting the field IDs/XPaths of items within the Web App.

But now I'm stumped on how to put it all together. I downloaded an action from the forum to click at an Xpath, but it has to be within Chrome or Safari, and it doesn't seem to recognize the Web App as Safari (understandably).

For the record, I'm sure I could do this from the project app opened as a webpage to the schedule (as a webpage) but I vastly prefer using the project app as a desk app rather than a webpage—so really want to see if there's a more natural way before resorting to that more cumbersome route.

Is there a good way to create an automation that identifies (and copies to named variables) fields within the Web App to then paste into a webpage?