Hi @noelt.dolan,
Yes, this is possible with Auth0 Redirect Actions. You can redirect your users to an external page where you gather their consent and store it in the user’s user_metadata.
You can also selectively trigger this based on some criteria, such as, their login count, like during their first time logging in.
You can append the user’s user_metadata as a custom claim after the redirect has completed and this way that information can be retrieved during the same session flow.
Here is a reference using Rules. You will have to convert it to an Action:
Let me know how this goes for you.
Thanks,
Rueben