Automagic Forum

Provide a possibility to hide all flows, widgets, global variables, actions and conditions by switching to a different profile. When copying flows or widgets, provide a way to copy them to a different profile. Any created flow, widget, action, condition or global variable is local to the current profile only. Flows in non-active profiles will not trigger in response to events.
Possibly provide an action to switch profiles (supposedly last action in a flow), thereby rendering all flows of current profile inactive, and activate flows in profile to switch to (without actually changing the flow enable/disable state). Provide a trigger which fires when a profile gets activated.
Several usage scenarios can be imagined for these profiles. Among those the possibility to test flows/widgets in a pristine environment before publishing.

You could use the setting Main data directory in the preferences of Automagic to switch to another profile/workspace. Automagic will initially copy the existing flows/widgets to the new directory but you can then remove the things you don't need. Automagic should ask to load the existing flows/widgets when switching back to another directory containing flows/widgets. I have not tested to switch back and forth many times but theoretically it should work
It does not provide every feature of your request but it might be helpful anyway.