You can create a custom stream target for Facebook in the Wowza Video platform.
In order to create a custom stream target please go to the Transcoder of the Live Stream and then Output & Targets. Once there please select the "Add a Stream Target" option.
And click on the "Custom".
Once there you can add the options below:
Target Name: Custom unique name
Provider: RTMPS
Primary URL: live-api-s.facebook.com:443/rtmp
Stream Name: Stream Key obtained from Facebook Studio
Once added you should have a green check mark against the target meaning connection is established.
Whereas, on the Facebook Studio https://www.facebook.com/creatorstudio If you see the video source connected it also means a connection has been made successfully.
Then you can complete the post details and Go Live using Facebook Studio.