Short answer: you don't.
Longer answer: Cordova plugins aren't available anywhere else but inside a Cordova app. If you want the same app to work solely in a web browser, then you'll need to implement workarounds to the Cordova-specific features that you're using. For example, you could use Web SQL Storage when running in the browser, but do be aware that it has significant limitations, is deprecated and may disappear, and isn't supported on all browsers anyway. In that case, you'd need to provide different adapters so that you could use SQLite in Cordova but perhaps use IndexedDB or something else when running in a browser. For everything else, well, you'll need to find a web solution. For example, social sharing -- you'd need to integrate with the social networks you want to use and share with them directly (providing any needed UI).
Regardless, you're going to need to know if you're running in a Cordova environment or in a browser environment, and then switch code paths as necessary in your app. The easiest way is to just have two different build processes, one that builds your PWA (and injects a value that indicates it is running in a browser), and the other that builds your Cordova app (and injects a corresponding value that you're using Cordova). There are lots of other ways too; a google search should turn them up.