I found this article looking for visualizations:

Microsoft is Adding Visualizations, Equalizer, and More to Groove Music - Thurrott.com

They're demonstrated there...

It says "At this time, there are two types of visualizations", however, I can't figure out where to enable them.

Has anyone found this or found a secret way to enable them if they're actually there?

It seems like Microsoft built the feature but it's not finished or not activated yet... I'd love to use the default music player but seems like Windows Media Player is still miles ahead (as buggy as it is).