Great place to ask the question!
Yup exactly
The bulk of the translations are located here: https://github.com/strapi/strapi/tree/master/packages/strapi-admin/admin/src/translations
But some of the plugins do have their own translation keys, in the case of the Draft & Publish those would be in the content-type manager: https://github.com/strapi/strapi/tree/master/packages/strapi-plugin-content-manager/admin/src/translations
Or the content-type builder: https://github.com/strapi/strapi/tree/master/packages/strapi-plugin-content-type-builder/admin/src/translations