It is possible to create an interactive Before/After component by BM Content builder(from v3.14) like the below video.
How to create a Before/After?
The features come from Slider module.
To find the Slider module, Please go to “Pages > Add New”, click “BM Content Builder”
Select Slider:
You will find there are 4 options for Style, choose the 4th style:
Click Add new image to upload an image for 1st slide, you can pickup an image(jpg, png, or gif) from local computer or pick up one from WordPress media library. The Before/After needs 2 images, click Add Slide to add 2nd image by the same way. More images will not be displayed.
Image Width – The percentage width that the image occupies in the container of the slider module itself. The 1st is for desktop, the 2nd is for mobile layout.
Alignment – The alignment of the image in the container of the slider module itself.