I know there is a way to translate the popups to a different language, but what about the layer names or field names?
I don't think this is a supported feature, for anyone viewing this post here is the Ideas page associated with it,
I had a look and there seemed to be an enhancement logged for this previously which was then closed as a known limitation to be able to accurately translate all the data that come with a map along with data values is currently not possible. Instant apps offer a solution for this but does not cover all the data and requires users to handle this
https://www.esri.com/arcgis-blog/products/instant-apps/mapping/arcgis-instant-apps-language-switcher...
https://www.esri.com/arcgis-blog/products/instant-apps/mapping/using-arcade-to-translate-pop-ups-for...