Check out the Kafka support in Testcontainers: https://www.testcontainers.org/modules/kafka/. It is container-based, but with a very simple-to-use API for spinning up Kafka in tests.

If you truly want something embedded, Debezium's KafkaCluster could be interesting: https://github.com/debezium/debezium/blob/master/debezium-co....

It's used four our own tests of Debezium, but I'm aware of several external users. It spins up AK and ZK embedded. Disclaimer: I work on Debezium