I use Edit Studio 4 for video work and so can only speak from my experience with that package. However, what you require can be achieved in ES4 without a plugin and may be adaptable to the editor you use: -
1: using a grahics editor that can support PNG format (I use Paint Shop Pro eight) create a graphic with a block of colour (or your chosen background) on the right, the banner you require along the bottom and a transparent area on the left through which your video will show;
2: save this as a PNG file with transparency;
3: place the graphic created above into the timeline of ES4 with the film of your product in a video track underneath. You should be able to see the video through the transparant bit of the PNG file;
4: the product description can be written in ES4s text editor in a video track above the PNG file and the text, PNG image and underlying video can be moved about and resized to get the placement required on the screen.
Alternatively, you may find the video package you use supports alpha channels or transparent GIFs. If not, look at the possibility of a 'matte', which on ES4 works in a similar way to masks in Paint Shop Pro etc - you create an image consisting of just pure black and pure white, where black can be assigned to one video track (the banner/description image) and white to the underlying video. This means you'd need to create a matte in the graphics editor with a white block the same size as the left 'video space' and a black section the same size and shape as the right bit and the banner. The text can still sit on top of the whole lot.
Hope this is of some use - it's really not as complicated as it sounds (I actually did all this for the first time myself last night)!