In the name of Allah, the most Beneficent, the most Merciful. 

It is permissible to say Joseph instead of Yusuf Alahi Wasalam or Jesus instead of Esa Alahi Wasalam in such a situation where there is a possibility that the audience will not know whom the Prophet is if you have used the Arabic name. However if the audience are all Muslims then it will be preferable to use the Prophets Arabic name.

Only Allah Knows Best

Mohammed Tosir Miah

Darul Ifta Birmingham.