Is a child born from an intermarriage between a Mongolian and a Han Chinese of mixed blood?

Strictly speaking, they are not mixed because they are of the same race.

Physical Characteristics of the Mongolian Race

The color of the skin is yellow or yellowish-brown among all the races of the world. Hair is mostly black, straight and stiff, with a slight curl in some; a few have light-colored hair. Beards and body hair are not well developed; faces range from flat to long and narrow. The chin is not protruding, but some are pointed, others flat. The cheekbones are prominent. The nose is of medium width, with a low nasal bridge; the lips are moderately thick, most of them protruding slightly forward; the eyes are moderately wide, with brownish eyes, a well-developed upper eyelid crease, most of them with a medial canthal fold covering the lacrimal caruncle, and the outer corners of the eyes are generally higher than the inner corners of the eyes. The skull is characterized by a medium nasal tip point index and high orbits. The Amerindian face is not as flat as that of the Mongolian races of Asia, and the nose is slightly more prominent. The shovel-shaped structure of the lingual surface of the upper incisors is also one of the distinctive features of the yellow race.

Distribution of the Mongoloid race

The Mongoloid race is not the most populous race in the world. The pure Mongoloid race is found in China, Mongolia, Korea, South Korea, and Japan in East Asia; and in Bhutan and Sikkim in South Asia; this is the Neo-Mongoloid race, or Northern Mongoloid race. In Southeast Asia, they are found in Burma, Thailand, Laos, Vietnam, Cambodia, Malaysia, Indonesia, Singapore, Brunei, the Philippines, and East Timor. There are also significant numbers of yellow people in Russia, Nepal, India, and the countries of the Americas. The other yellow race in Southeast Asia, except for the Chinese, is the Malay race

Also, the Mongoloid race started migrating around from East Asia from 20,000 years ago. So, today's Central Asia, West Asia, South Asia, Eastern Europe, Central Europe, Northern Europe, a lot of peoples are yellow-white mixed race. In Southeast Asia, the Pacific Islands, and Madagascar in Africa, many peoples are of mixed yellow and equatorial races. After the geographical discovery, the Mongoloid race in the Americas and the white people again occurred extensive hybridization, this phenomenon is more obvious in Latin America.