For Cubase 15 Pro I had to copy the “Flow” folder to the “User Preset Location”:
/Users/username/Documents/Steinberg/Cubase/User Presets/Project Logical Editor/Flow
Tip: If you open Cubase go to Project → Project Logical Editor → Setup
Then click on Preset → No preset → Show “User Presets Location” - now the finder opens the correct path.
Now restart Cubase, done! 