Is your OmniScript running from Lightning or Experience? [EP-27]
In this brief video I point out that you can use %ws% to determine whether your OmniScript is running from Lightning or Experience.
I don't have Experience in my developer org so I had to demonstrate from an org that I don't have access to edit.
In your OmniScript, add a SetValue component with: ws = %ws%
If ws != null, then your OmniScript is being run from Lightning. If ws = null, then your OmniScript is running from Experience.
Use this in a visibility condition to show components/steps based on where the OmniScript is running from.