Options for Redirecting to another app

The scenario that i am trying to solve:

User logs into a mobile application, and can use the app. The mobile application is setup with a dedicated Application within Auth0.

I want to open a web view from the mobile app, that opens a website, that provides a supporting function, but is not part of the mobile app itself, it is a hosted web app. The web app is also restricted with Auth0, using a dedicated auth0 application.

In an ideal world, i’d like the mobile app to issue a delegation token, that can pass the authenticated user credentials to the web app, and the web app can then use this to get an access token - however i’m not finding any suitable functionality to achieve this in any way.

Does anyone have experience with anything similar? or could provide guidance.