water marks
 

How to achieve this?

Put a transparent graphic on a layer above your video.

You can also use a regular graphic and lower the track opacity.

and then wait....
 

and wait.... and wait. Just as a warning, any time you put a transparent layer (I've done this many times) on top of our video you can expect render tiems to balloon up 2x or more. I had an editing cut for an auction house with time codes & clip names but I put the time codes in the corner with an opaque background so t would stand out. Mistake. It took about 4hrs to render out that video when there was NO color correction and no effects.

Just an FYI