Hey everyone, the Nintendo Direct was held earlier and content from Castlevania was revealed including characters, a new stage, and music.
While showing the stages bosses, they did reveal that Medusa will be in the game and appear as a boss on the Castlevania stage. While we don't get to see her in action, she shows up briefly here:
https://youtu.be/P-kQWJrjRV4?t=4m28sAlso near the beginning in a cutscene at 0:38.
While nothing is confirmed, it looks like we can definitely expect petrification in this game! Let's hope the effect is good!

Be on the lookout for demos or early access footage of this stage!