I am wondering the same.
This is an update post from september 26, 2017.
LumaFusion 1.4.3 is now available in the App Store. This version includes important bug fixes since 1.4.2:
* Fixed export error that could appear incorrectly in some exports
* Fixed issue where some video clips would be imported with a very short (incorrect) duration
* Fixed crash that could occur when quickly trimming clips in the timeline
LumaFusion 1.4 is an incredible update with dozens of powerful new features and improvements
New Audio Pipeline with New Audio Tool Features:
• Stereo configuration for clips (fill from left, fill from right) for dual microphone recordings
• Audio Ducking: set master and auto ducking flags for clips, and adjust ducking parameters in project settings
• Panning: Pan stereo audio clips between left and right channels, and keyframe panning
• Keyframe audio volume and panning during playback
• Improved waveforms on timeline clips
• Audio Effects, including 3rd party Audio Units are now supported in LumaFusion
• Improved audio meters with dbFS range
• Audio mixer now switches between hidden, all tracks, and master volume only modes
• Solo/Mute buttons in the LumaFX audio tool
I have tryed to send them a personal email, and i am waiting for their response. Seems a bit weird to me to remove such a huge feature without letting people know?
The only other topic i can find about it, was the same question, and the answer was that they where looking in to bring it back around the end of the year (2017) - buuut it is not here yet