Star%

Star% is a short category on the Category Extensions boards for Super Mario Odyssey. The category involves getting to the Mushroom Kingdom as fast as possible and collecting a Star.

Route

Mushroom Kingdom Painting

The route for Star% is the same as Any% up through the Sand Kingdom. However, at the end of Sand Kingdom, Wooded Kingdom must be selected first so that the painting in the Lake Kingdom leads to the Luncheon Kingdom.

Location

If you have the 1.0 version of the game, you can execute the Bruncheon trickjump, allowing them to access the mainland early. The player must then make their way over to another painting on the opposite end of the kingdom, which in turn leads to a floating island in the Mushroom Kingdom where a Star can be collected. 

From other versions of the game you'd have to make your way through the game all the way to Luncheon by regular means.