Inspection characteristics mass translation

Hi everyone,

In Quality Management, we would like to translate inspection characteristics. I understood that this can only be done through the UI by logging in using the concerned language. However, I have two related questions:

• Is there a way to mass upload them through REST API? It seems like it cannot be possible but I am looking for a confirmation and maybe a useful workaround 
• How to do so when the characteristic has already been included within an inspection plan? We are implementing one region at a time and we did not manage the translations for every implemented language at first.