Scholars have differed regarding whether performing an optional Hajj on someone else’s behalf is legislated. There are multiple positions, the strongest two of which are:
The first position: It is not permissible to perform an optional Hajj on someone else’s behalf unless they are deceased or an invalid  An invalid is someone handicapped in such a way that they are not expected to recover. . This is the position of the Shafi`i  They predicate that Hajj on behalf of the deceased be per their request only. school according to the soundest position as well as a narration from Ahmad. This is the chosen position of al-Shinqiti and Ibn Baz.
The second position: It is never permissible. This is one position amongst Malikis and Shafi`is. This is the chosen position of Ibn `Uthaymin.