You can come close to doing what you want using the DDM command-line processor and ordinary Windows shortcut hotkeys.

ddm.exe /SetControl E9 00      //*turn PIP/PBP off

ddm.exe /SetControl E9 21      //*switch to PIP small

ddm.exe /SetControl E9 22      //*switch to PIP large

ddm.exe /SetControl E9 23      //*switch to PBP aspect ratio

ddm.exe /SetControl E9 24      //*switch to PBP fill

I don't know how to use the DDM command-line processor ...  I'm not much of a computer guy

1. Find the Dell Display Manager (DDM) application in the Windows Start menu

2. (Win7) Right-click drag the DDM item to the desktop and choose "Create shortcut here" from the popup menu

or

(Win10) Drag the DDM item to the desktop

3. Right-click the new DDM shortcut file on the desktop and select "Properties"

4. In the Properties dialog, find the text box labeled “Target” and append " /SetControl E9 00" (w/o the quotes) to whatever is already in there

5. Then find the text box labeled “Shortcut key” and enter the keystrokes you want to use as your hotkey

6. Click "OK"

Repeat steps 1 thru 6 to create a 2nd shortcut to DDM, but this time at Step #4 change the "00" to one of the following values:

21 for PIP  small

22 for PIP large

23 for PBP aspect ratio

24 for PBP fill

Do you have PIP/PBP commands for UP2516D? ddm.exe /SetControl E9 XX is not working for my UP2516D. Thanks in advance.