Google Play shows Unoptimized APK for Cordova App

Well, it's just a warning I think. You could ignore it and rollout the release. The problem is that you haven't completed and provided enough information for important contents like store listing, content rate, pricing & distribution, and app release. When all of them show "green check", you could rollout the app.

This is just a warning, and you can carry on uploading Cordova APKs. The Cordova team know about this, and you can follow their feature request to support Android App Bundle here