Imam Nawawi rahimahullah said:
“I say: The Scholars agreed upon the recommendation of beginning the supplication with praising Allah, the Exalted, and glorifying Him, then sending blessings upon the Messenger of Allah (ﷺ). Likewise, completing the supplication with them. The narrations in this chapter are many and well-known”.
[Al-Adhkaar pg. 118]
Imam as-Sakhaawi rahimahullah said:
“As for sending blessings upon the Prophet (ﷺ) in the beginning of the supplication or the middle or the end, then the Scholars have agreed upon the recommendation of beginning with the praise of Allah, the Exalted, glorifying Him, then sending blessings upon the Messenger of Allah (ﷺ). Likewise completing the supplication with both wordings”.
[Qawlul-Badee’ Fi Salah ‘alal-Habeeb ash-Shafee’ (1/221)]
Shaikh al-Albani rahimahullah said:
“One should sometimes send blessings upon the Messenger (ﷺ) due to what will be mentioned later”
[Night Prayer pg. 17]
Also it is reported:
عَنْ عَبْدِ اللَّهِ بْنِ الْحَارِثِ، «أَنَّ أَبَا حَلِيمَةَ مُعَاذًا كَانَ يُصَلِّي عَلَى النَّبِيِّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ فِي الْقُنُوتِ
Abdullah ibn al-Harith said: Abu Haleema Muadh radiallahu anhu used to send blessings upon the Prophet (ﷺ) in the Qunoot”
[Reported by Ismaail ibn Ishaaq al-Qaadi in Fadl Salah ‘ala Nabi pg. 89. Shaikh al-Albani said in the tahqiq of the book: Saheeh Mawqoof. He was Abu Haleema Muadh Ibn al-Haarith al-Ansaari. Ibn Abi Hatim said: “He was the one Umar appointed to lead them in the Taraweeh in the month of Ramadan”]
So it is allowed sometimes to send peace and blessings upon the Prophet (ﷺ) in the Qunoot. As for beginning with the praise of Allah, then it was not reported in the dua of Qunoot. It is best to recite the dua of Qunoot the way the Prophet (ﷺ) taught Hasan ibn Ali radiallahu anhumma.
And Allah Knows Best
Faisal Ibn Abdul Qaadir Ibn Hassan