Text popup on button hover

Site URL: https://scottlorenzen.com/industrial-photography

I am in the process of refining the design of my Squarespace photography website: https://carreonphotography.com, and I am wondering what sort of plugin I could use to implement a text popup on hover over a button like this website: https://scottlorenzen.com/industrial-photography  Example also included.

The text displayed is not alt text but more like a caption.

I also need to minimize the footprint of my text which is only in place for Google SEO. I was thinking of using some accordion function or sliding text blocks. My clients don't much care for the text because they are looking for a commercial photographer; not a retail wedding photographer. 

Any thoughts on plugins or coding that I could implement to do this would be greatly appreciated. 

For my next design phase, I will probably just hire a designer.