As to my knowledge DH key agreement uses public and private keys to generate a session key between two parties and uses that session key to encrypt the data. Isn't this the mechanism used in Hybrid encryption as well?
Hybrid encryption uses public-key cryptography to exchange a secret key, and symmetric cryptography to encrypt the data. The main reason is that public-key cryptography makes the key exchange easy, while symmetric cryptography is faster.
The Diffie-Hellman key exchange is a protocol used along with public-key cryptography. It allows 2 entities to create a shared secret (i.e. the session-key). The DH key exchange will not encrypt your data! It will only give you a key that can be used with a symmetric-key algorithm to encrypt the data.
Basically, the DH key exchange is one of the tools used in the first steps (the key exchange part) of Hybrid encryption.
PS: I found a related question on the Crypto community, you might want to take a look:
"Why is Diffie-Hellman considered in the context of public key cryptography?"