Veganism is the practice of abstaining from the use of animal products, particularly in diet, and an associated philosophy that rejects the commodity status of animals. A follower of the diet or the philosophy is known as a vegan.
as salam alaikum
it has been reported that the Messenger of Allah, peace be upon him and his family, said:
عليكم باللحم فإنه ينبت اللحم و من ترك اللحم اربعين يوما ساء خلقه
"You should eat meat because it makes meat grows. Whoever abandon eating meat for forty days will get blameworthy traits".
The hadith has been reported from various sources belonging to different Islamic schools with slight variations of wordings.
Although there is no clear prohibition on veganism, from the above-mentioned hadith and other indications from the Qur'an and Sunna we understand that it is not the ideal diet for a Muslim.
With prayers for your success.
The Muslim Must follow the Prophet Muhammad (SAWA) and his Progeny Ahlul Bayt (AS) in every matter in life including eating. We can not claim that eating meat is absolutely wrong and make is forbidden on us, because this claim contradicts with the life and practice of the Prophet ( S) and Ahlul Bayt (A) who used to eat meat. Even in Quran, Allah (SWT) ordered us to eat from the meat of the animals that we sacrifice (Sura Al-Hajj, Verse 28 and Verse 36). If eating meat was absolutely wrong, we would have never seen such an order in Quran to eat from the meat of the sacrificed animals.
Islam teaches us not to eat more meat as we read in Hadeeths that it is Makrouh ( disliked) to eat meat daily for forty days, and it is Makrouh ( Disliked) to leave eating meat for continuous forty days. It is mentioned in the Hadeeths that such persons who either ate meat or left eating meat for forty days need Azaan to be recited in their ears to remove the harm from them.
Muslim can not be completely vegetarian or vegan because it is against Quran and the life and practice of the Prophet (S) and Ahlul Bayt (A) and it can suggest that they were wrong by eating meat.
We can eat little Halal meat but Not leave eating meat totally which is Haraam, or for forty days which is Makrouh ( disliked).
In short, we need in every matter in our life including eating, to follow our Prophet (S) and his Progeny (A) and not others.