Several options...
The easiest way is to use an ImageView or B4XImageView for it. Then evaluate the ClickEvent of the ImageView as ButtonClickEvent.
If you need an animation, you can also use an animated GIF file.
Of course, this option has certain limitations compared to a regular button when it comes to the ‘pressed’ state, etc. You will have to program these things separately.
Of course, you can also use a regular button to which you can then assign separate layouts using the Designer.