Hanafi
The sources give no view for it here.
الوصية لغير الوارث
هل تشرع الوصية لغير الوارث؟
Each school’s answer
In our wordsHanafi
Not stated in the sources
Maliki
Not stated in the sources
Shafi'i
Not stated in the sources
Hanbali
Not stated in the sources
The texts
الْوَصِيَّةُ لِذَوِي الْقَرَابَةِ: ١٦ - أَجْمَعَ الْمُسْلِمُونَ عَلَى مَشْرُوعِيَّةِ الْوَصِيَّةِ لِغَيْرِ الْوَارِثِ، أَمَّا الْوَصِيَّةُ لِلْوَارِثِ فَقَدْ جَرَى فِيهَا اخْتِلاَفٌ وَتَفْصِيلٌ يُنْظَرُ فِي مُصْطَلَحِ (وَصِيَّة) .
«الموسوعة الفقهية الكويتية» (Kuwait) entry «قرابة» vol. 33 p. 74
From the schools’ own books
Maliki
The sources give no view for it here.
Shafi'i
The sources give no view for it here.
Hanbali
The sources give no view for it here.
What is «in our words» is our standard wording; the books’ texts stay as they are.