This is a bit of fun. Cappella software makes an app, “tonica fugata”, that supposedly creates counterpoint, fugues, and harmonizes the style of Bach, etc.
There’s a ‘Turing Test’ on the site (in German, but easy enough to navigate). Guess whether the chorale is by Bach or by the machine!
I got 9 out of 10, just by intuiting that something wasn’t quite right. (The one I got wrong clearly wasn’t one of Johann’s strongest.)