From my point of view "Although" can be translated also as "Deși". Also the verb to be has two forms (ea)e /(ea) este
Another translation would be:
Deși ea este mică, ea lucrează din greu.
Is this translation actually correct? If she works hard, she's hard-working, dilligent. But it says that foarte greu means "with great difficulty."
You're right. You could say "ea lucrează din greu".