Deployment error regarding translations when generating package version

There are two things you have to do:

  1. enable Translations in your Scratch-Org-Def (I guess, you already did).
  2. let package-version-create use this scratch org def (I guess, that you didn't)

So you scratch org def should looklike this:

{
  "edition": "Enterprise",
  "language": "en_US",
  "features": [],
  "settings": {
    "languageSettings": {
      "enableTranslationWorkbench":  true,
      "enableEndUserLanguages": true
    }
  }
}

And your package-Version-create like this:

$ sfdx force:package:version:create  -f config/<your scratch-org-def>.json