I use ScreenFlow a lot for screencasts, but also for general video editing. I just discovered this on their website:
We are actively updating ScreenFlow to be compatible with the new Apple Silicon hardware. The completion of this work depends on several of our integrated partners updating their applications as well.
At this time, ScreenFlow does not work under Rosetta emulation. If ScreenFlow is a critical application, we recommend holding off on transitioning to the new Apple Silicon hardware until we have a more concrete release date.