Es.json do not have enough field to translate

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser):
Opensearch-Dashboard 2.12.0
Index-Management 2.12.0
dashboards-i18n

Describe the issue:
When I applied my file ja-JP.json has been translated from English to Japanese, it’s working fine but all text in Index-Management screen do not translated because the file en.json only contains field for Opensearch-Dashboard, not include fields for plugin. Can someone help me on this case pls!

Configuration:

Relevant Logs or Screenshots: