How could I best insert this laser effect?

I'm having trouble editing a video, I know how to add in a simple laser effect like so:


By simply having an image of a beam and placing it and moving it so it fits on the video for one frame.

But I'm having a bit of trouble on other views like this:


Maybe this is really stupid, but how would I best do this? Is there maybe a better way than just adding an image?

Thanks.