Final answer:
The typical keyboard shortcut for adding a transition to only video is Ctrl+D on Windows or Cmd+D on macOS, and this can vary with different video editing software.
Step-by-step explanation:
The keyboard shortcut for adding a transition to only video in most video editing software is typically Ctrl+D (on Windows) or Cmd+D (on macOS). It's important to note that shortcuts can vary depending on the software being used, such as Adobe Premiere Pro, Final Cut Pro, or others. To apply a transition to only the video and not the audio, you might need to make sure that only the video track is selected or locked depending on the program's functionalities.