What is the authenticity of the hadiths mentioned regarding raising the hands in supplication after prayer, and does this contradict what is stated about this act being an innovation?

The hadiths mentioned in the question are weak in their chain of narration (isnad): 1. The hadith of Anas is very weak due to 'Abd al-'Aziz ibn 'Abd al-Rahman. 2. The hadith of 'Abdullah ibn al-Zubayr is weak due to the discontinuity (inqita') between Muhammad ibn Abi Yahya and 'Abdullah ibn al-Zubayr, and the weakness of al-Fudayl ibn Sulayman. 3. The hadith of Abu Hurayrah is weak due to 'Ali ibn Zayd ibn Jad'an. 4. The hadith "Prayer is two by two" is weak due to 'Abdullah ibn Nafi', who is unknown (majhul).

Even if some of them were to be considered authentic, it would be due to an incidental matter, not a regular, established guidance.