I think you may be mixing concerns a bit. Also, the authentication mechanisms for various tools may not necessarily play well with another, and/or you may need different intra-service auth vs. public-facing/customer sessions/tokens. If you need to have disparate tools authenticate to one another with a bearer-type token mechanism, consider Vault. It has excellent support for at least one of the tools you mention (RabbitMQ.)

For flexible token auth, JWTs.