Hi Pradeep,
The translation feature works for buttons and labels too.
Here follows my example (my test system runs kernel 7.42 pl 412 + Personas 3.0 SP03):
Flavor "Test" being called with sap-language=en:
Flavor "Test" being called with sap-language=pt:
Translation screen (it is in display mode) in /personas/admin:
What is preventing you from translating labels and buttons?
Kind regards,
Cris