Mauritians do not need a visa to visit any Schengen country. However, they need to be in possession of certain documents like insurance cover, invitation letter or hotel accommodation confirmation and return ticket back to the country where currently residing. However, if you have residence permit in UK or Ireland, it could happen they may not ask you for any documents.
No nt anymore dear mauritians
I don't think,,,
If they have a visa for Ireland only , yes they do need a visa to visit another European country but they should check with the embassy of the country they wish to visit and explain their situation .