What is Imam Shafi’s opinion regarding reciting the Fatihah behind the imam after he finishes? Is it similar to the Hanafi school (they say the imam’s recitation Fatihah is sufficient)?
Wa alaykum salam wa rahmatuLlahi wa barakatuHu,
In Tuhfah 2/44, Ibn Hajar stated that reciting Surat al-Fatihah is obligatory in every rak’ah of every prayer. This applies if one is praying alone, leading another, or following another. The evidence for this ruling is the rigorously authenticated hadith, “There is no prayer for one who does not recite ‘Fatihat al-Kitab.’”
There are hadiths that indicate to the imam’s recitation being sufficient. Like the words ascribed to the Prophet (upon him be peace), “Whoever has an imam, so the imam’s recitation is for him recitation. Man kana la imam, fa qira’at al-imam lahu qira’ah.” However, many hadith scholars judged it weak, like Imam Daraqutni in his Sunan. Daraqutni stated that the narration is mursal.
Allah knows best. Source: https://islamqa.info