We can now add multiple language content files under a single content folder through the Migration process as below :

We are required to enable the multi-locale migration option from the backend for that migration project. Please drop a mail to learningmanagersupport@adobe.com and share the project ID. You can fetch the project ID from below :

Integration admin>>Migration>>click on the project>>

Once we enable it from the backend, in the module version CSV, we should not mention the module version in the module version CSV file.

After we run the module and module version CSV, we can see that both the language content files will be under same content folder as shown above.