Craete a mail forwarder in a Docker container. Should be a quick and simple solution.
Add SMTP mail functionality to the official Docker WordPress image. See 2 examples of adding Postfix to Wordpress in a separate container. Learn how to add Postfix to the same container with a Dockerfile. Learn how to set DNS/rDNS records to increase outbound mail deliverability.
Use a Dockerfile to add XDebug to the official Docker WordPress image. Do not want to build? Use a pre-made image from a repository on Docker Hub. Also, see how to configure PhpStorm for debugging. And finally, learn how to separate production and development environments using multiple docker-compose files.