I've done this in a few of my videos. This one is pretty much exactly the same as in sunny and pretty easy to do. However, I used final cut to do it in mine. Il explain how I did it as maybe premier has the same workflow. If it does't then sorry but you may get some sort of inspiration.
So I basically just used the crop feature on final cut pro. By selecting the video you want to ''swipe'' you bring it up in the preview window and hit the motion tab. You can then see the option to crop the video. I then selected the point where I wanted to start the swipe and finish it. Then I decide which way I want to crop. If im swiping to the right, at the start of the swipe I will keyframe the left crop but keep it at 0% crop so nothing changes. At the point I want the swipe to finish I keyframe a 100% crop to the left. When you play this back your video will gradually crop from your start to end point left to right. Am I making sense?
Then I put the video I want to swipe in on the timeline underneath the previous video. So when the swipe happens I now have the video underneath being revealed. To get the bars in between the swipes I just do the same as before and crop the 2nd video and keyframe each point so the crop leaves a gap in between the videos.
Thats pretty much it. That may not be the bet way to do it but its what I do. You just mess around with cropping and scaling the images to what you want to do. Whats key is to make sure you keyframe and you will work it out. I hope it transfers over to premier, im sure there will be something similar if not