Found an issue with aws.mwaa.Environment (could be just the docs) . Where is the best place to log issues?

The github repo for the provider, either https://github.com/pulumi/pulumi-aws or https://github.com/pulumi/pulumi-aws-native depending on which version of aws your using.

Whats the different between those providers?

The AWS Native provider is newer and uses AWS’ Cloud Control API, which doesn’t expose all AWS services and offerings. The AWS Classic provider is older but has broader reach/support. Using both in a single project is supported.