Residence Permit Expired

I am traveling with some young people from Portugal to Luxembourg for training. One of the young people is from São Tomé and Príncipe, and his residence permit has expired, but it was extended based on Decree-Law No. 85-B/2025, until October 15.

Does anyone know if he will need a visa to travel to Luxembourg? I have been looking for information, but it is not very clear. Tomorrow I will contact the embassy to find out more.