The Red and the Blue was an Italian stop motion animated television series for children. It has two characters, antagonistic shapeshifters, one colored red, the other blue. It is by Misseri Studios.
Misseri's website describes the situation as:
Two blocks of clay. The Red is big and passionate; he like driving fast cars, eating... enjoying all the pleasures of life. The blue is small, smart and cunning, and he's there just to bother the red.