Is there any way to have an image change on hover (from image a to image b) in wordpress? I wonder if there is a plugin or a custom function I can use to perform this.
P.S. -It is not a featured image for a post.
This isn't really a WordPress-specific question, but generally you can do something like this via CSS (depending on the structure of the image). Generally, you'll have an easier time doing this if the image in question is being applied as a background image to a DIV, rather than as just a standard img tag. Then, you can use the :hover CSS property to change the value for background-image.
See the accepted answer here to understand how to put this together: