Display On-screen Controls in Premiere Pro
Premiere Pro displays on-screen controls only if the effect header is selected in the parameter inspector:
1) Switch to the parameter inspector, and scroll to the effect whose on-screen controls you want to use.
2) Click on the effect’s name. Notice that the header as a whole becomes highlighted:
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3) The on-screen controls will remain available in the canvas / preview area for as long as the header remains selected.