A couple current hide/reveal tricks: (1) Minimize a card to its title (using the left arrow key), and reveal its content with the right arrow key. (2) Use Markdown syntax to blur out text; you can then hover over the blurred out text to reveal the text. The Supernotes cheatsheet lists the basic syntax explanations for that and other formatting features.
I’m not sure if v2 has any other flashcard or new spaced repetition features. You should check to see in the forum if that feature request has been made or implemented. --John