Yes, it is possible to use client ID for authentication in JSON Web Tokens (JWT). In fact, JWT provides several methods for client authentication, including client_secret_jwt and private_key_jwt.
The audience (aud) claim in a JWT is intended to identify the recipients of the token. The client ID in OAuth refers to the client application that will be requesting resources from the Resource Server. The client app will request a JWT from the Authentication Server, passing its client ID and client secret along with any user credentials that may be required. The Authorization Server validates the client using the client ID and client secret and returns a JWT. The JWT will contain an aud claim that specifies which Resource Servers the JWT is valid for.