Thank you for contacting us.
Unfortunately Shopify does not allow to translate the the names of the metafields.
The main thing of metafields like name: value is that name in this case could not be changed. Otherwise it will break the whole metafield since the name will be different. For example any additional language that you are adding is using the same metafields name as your original language, but the value could be different and if you change the name of the metafield it will be like a brand new one which you don't have in your Shopify settings.
The workaround that you are using is the only way to avoid it, to my regret.
Hope it helps!
All the best,