Check out 4 different image gallery hover animation effect using Swiper.js by Khanh. In the 1st vertical accordion like gallery when you hover over the image has a smooth slide pushing out the images around it to the side. In the second one the image zooms a bit out pushing the other ones to the side and has a background shadow giving it a bit of depth. In the 3rd one there is a bit of shake as the image settles into the expanded view. The 4th one is similar to the 1st one but is a bit smoother and has a shadow effect as well. You can scroll these all 4 different style.
If you are having trouble with the pen, try the archived copy on GitHub