I would recommend you to consider the JFrog Platform that includes JFrog Pipelines - it will allow you to manage the full artifact life cycle for your sbt, docker and other technologies, and automate all of your CI and CD using cloud native declarative yaml pipelines. Will integrate smoothly with all your other toolset.
There are many parameters towards your decision. CodeArtifact supports limited amount of package types, while Nexus is way more universal. More over, CodeArtifact can't be self hosted, if that's a current or future requirement of yours. I would recommend you to look at JFrog Artifactory as well, at the heart of the JFrog Platform, it is a fully featured, enterprise grade artifact management, built with strong metadata management, 100% automation enabled and fully hybrid.