We are releasing the ability to overlay images and videos in 4.24 next week! You can try it out now using the /next early access release, and we are looking to get some feedback on it. The functionality is even better than 3.x… you can overlay both images and videos in 2D and 3D, add/remove multiple images on the fly very easily, and use it with other 4.x capabilities like layer blending (note: so far you can only do layer blending with MediaLayers in 2D).
Here's a simple example: https://codepen.io/U_B_U/pen/MWQGWdb?editors=1000
Drop me a note and let me know how you will be using it 🙂