Is it permissible to wear trousers at home and in front of maharim if accompanied by a long blouse reaching the knees, as mentioned by Sheikh Al-Arifi?

It is forbidden for a woman to wear tight, form-fitting clothing in front of those who are not permitted to see her in such a state, except for her husband; as Allah the Almighty says: "And those who guard their private parts (29) Except from their wives or those their right hands possess, for indeed, they are not to be blamed (30)."

However, if a woman wears something over it that covers her attractive features, there is no harm in that. As for a blouse that reaches the knees, it is sufficient, but anything shorter is not; due to its failure to cover what must be covered in front of mahrams.