I’ve been working with Shortcuts from Apple since the days the software was called Workflow.
I wrote a number of shortcuts that pushed the limits of what could be done in Shortcuts in iOS 12 and 13, including Cronios, LaunchCuts, Autocuts, PromptKit, Inspector, and more. I also developed two Shortcut utility applications, LaunchCuts and MFC Deck, on the App Store. Unfortunately, changes in iOS 14.5 and iOS 15 caused these two programs to break, and I have made the decision to remove them for sale from the App Store.
My current focus with Shortcuts has been in my video production tool, MixEffect. There are over hundred actions that control nearly every aspect of Blackmagic Design ATEM switchers. Read the documentation on Shortcuts support in MixEffect here.