Is it permissible to say "Radiyallahu Anhu (May Allah be pleased with him)" for individuals other than the Companions, and is it a supplication?

The expression "radiya Allahu anhu" (may Allah be pleased with him/her), used to invoke Allah's pleasure upon the Companions, is a supplication for them. It is permissible to supplicate and seek Allah's pleasure for any Muslim, even if they are not Companions. This is the view held by the majority of scholars, who cite the verse: ﴿Their reward with their Lord will be Gardens of Eden beneath which rivers flow, wherein they will abide forever. Allah is pleased with them, and they are pleased with Him. That is for whoever fears his Lord.﴾ [Al-Bayyinah: 7, 8].

The practice of the majority of scholars has been to invoke Allah's pleasure upon the pious predecessors of the Ummah, other than the Companions. Imam An-Nawawi said: "It is recommended to invoke pleasure and mercy upon the Companions, the Tabi'in (successors), and those who came after them from among the scholars, worshipers, and all good people. So one may say: 'radiya Allahu anhu,' or 'rahmatullahi alayh,' or 'rahmullahu' and similar phrases." Contrary to those who restricted the invocation of pleasure to the Companions only, the correct view, held by the majority, is that it is recommended for everyone.

However, if the statement "radiya Allahu an fulaan" (Allah was pleased with so-and-so) is made as a statement of fact, it is not permissible to apply it except to the Companions, because Allah Almighty informed us that He was pleased with them.