System Network Extension

Hello,
I have watched the WWDC 2019 session about Network System Extensions. One of the use-cases presented for a Content Filter API is to scan traffic and decide if it should be blocked or not. Is it possible to receive decrypted HTTPS traffic from the applications installed on a system?
From my testings, I observed that the traffic is forwarded in its original form (encrypted for HTTPS, plain for HTTP) to my system extension.
My second question is related to NETransparentProxyNetworkSettings. How do I apply these settings in the NEAppProxy class? I did not manage to find a method such as apply or setRules.