Set corners when cropping video
Yes, you can. If you're in Final Cut Pro X you can use the "Distort" section of the inspector, or in Motion, you can use the "Four Corner" function in the Inspector when your video is selected. (In Motion it will be in the Properties tab.) The same functionality is available via the on-screen controls, which are easier to use than entering values by hand.

I believe that After Effects and Premiere have similar functionality, though I don't remember the details off the top of my head as it's been a few years since I used them regularly.