System Error messages (Validation Messages) Translation

Platform : 10.0.405.0

Cloud based environment

I am trying to translate System Error Messages (Validation Messages) in to Spanish language for Mobile

I am using Multilingual Plugin and json object in Mobile


My locale is set to "es"

All other translations are working except for this built in validation messages.

Hello Archit. Can you provide a sample espace to check how you're doing it?