Here is a white ceramic mug with Movie Baby Sonic design. It has the CG 'holding a sunflower' art of him on one side, and the logo with background of lighter logos on the other. The graphic side spells out Baby Sonic in Japanese, maybe to add a bit of an 'exotic' appeal to the cutsey art. (The movie really pushed the baby-form hard in advertising in Japan because it was never shown as the blue/troll/erased version and they felt people would be more open to it if they could show something cutsie-poo on merch rather than how he is normally.)
The mug is a Sega Shop online exclusive, and about 20 dollars. It was released around the same date as the movie.