Cannot override screenshot hotkey from editor in packaged game

The F9 hotkey for screenshots cannot be overridden in blueprints. Even removing the hotkey from the Editor Preferences>Keyboard Shortcuts list does not prevent the shortcut from being used in packaged projects.

Regression? (No), issue (does) occur on 4.10.4

1. Open Editor (third person blueprint)
2. Open third person character blueprint
3. Create event "f9"
4. Add a print string node to event
5. Compile>Save blueprint
6. Save level
7. Open File>Package>Windows>Win64
8. Open WindowsNoEditor in saved filepath
9. Open project .exe file
10. Press f9

Results

Screenshots are taken, no print string appears. You can find the screenshots in \WindowsNoEditor\PROJECTNAME\saved\screenshows\WindowsNoEditor

Expected

No screenshot is taken, print string text 'Hello' appears in top left of screen