All the options you listed are viable, but each comes with trade-offs. The WebView approach is the easiest and quickest—perfect if your Vue3 website is fully responsive. Users can log in and use it like a native app, but performance and offline support may be limited. Converting Vue3 code into a native app using tools like Capacitor or Cordova is a more flexible and robust choice. These tools allow you to package your existing front-end and interact with device features, making it feel more like a true app while still using web technologies.

Embedding your front-end files directly into the app is similar to the second option but requires you to rebuild the app for every update—less ideal for frequent changes. However, it offers more control and can work offline.

In terms of learning curve, WebView is the easiest, while using Capacitor or similar tools has a moderate curve but offers better scalability. For modern android app development, combining Vue3 with Capacitor is a solid middle-ground: you retain your existing codebase and get native features.

If you're planning long-term support and features, avoid pure WebView and go with a hybrid solution like Capacitor.