I tried out the partnerspacemanager and managed to get the phone app in the left ambience drawer. Didnt find any conversation about this which is suprising because its very easy to do at least for the phone app. Just make a partnerspace.json file like told in documentation in github and direct the qml to for example /usr/share/voicecall-ui-jolla/main.qml and it works. Only problem is that the pulley menu shows wrong text but it still works normally.