If some people believe that Imam Ali (as) independently created Prophet Adam (pbuh), it will be against the Quran and considered shirk. Not to mention that the creation of Adam by the physical body (hands) of Imam Ali (as) doesn’t comply with existing realities, because his body was created after Prophet Adam’s and in a totally different time, making him one of Prophet Adam’s children and descendants.
Of course taking into consideration the fact that sometimes creation is done through the mediation of others, and there are hadiths that maintain that the light of the infallibles existed before the creation of Adam (pbuh), believing that his creation took place through the mediation of their light won't be shirk and in conflict with Islamic fundamentals, although such a belief itself isn't considered one of the fundamentals of the Shia school of thought, thus more research can be done on it.
What is for sure is that according to what one of the verses of the Quran clearly states, Allah (swt) created Adam (pbuh) with his own ‘hands’. This verse and its content are accepted by all Shia scholars and interpreters, leaving no room for any doubt.
On the one hand, after doing a general search in our hadiths, a hadith identical to what you mentioned in your question wasn’t found, but in the future if we stumble upon such a hadith, we will discuss its authenticity and chain of narrators. Also, if you have the Arabic of the hadith, please send it to us so that we can give a more precise answer to your inquiry.
Anyhow, considering other hadiths and Quranic verses, we must say: keeping in mind the following premises, the creation of Prophet Adam’s (pbuh) earthly body through the light of the imams (as), of course with another explanation other than what might be common amongst people, is something possible and will not clash with the verse we mentioned either.
We would like to draw your attention to these premises:
1- According to the Shia and many of the Sunnis, Allah (swt) bears no material body allowing us to say He is made of different parts and consider Him similar to other beings and creatures. That’s why we can't take some Quranic verses that attribute physical parts such as a face, hand, foot, eye, ear, etc. to Him for their literal meaning and are actually figures of speech that have an inner meaning and must be interpreted as Allah’s (swt) knowledge, power, existence, etc. This is why for instance when it is said that Adam (pbuh) was created by the hand of Allah (swt), what is meant is that he was created by the power of Allah (swt).
2- In many cases, Allah (swt) attributes what others apparently have done themselves and with their own hands to Himself, for example, He says that He is the one who provides the people with ships, although we all know that it is man who builds the ship, not Allah (swt)!
Of course, since man’s power is in continuation and a part of Allah’s (swt), explaining such a verse and understanding its true meaning isn't difficult, and in a sense, man and everything he has made are in reality, a creation of Allah's (swt).
3- According to some ahadith, the creation of the light of the imams (as) has taken place before the creation of Adam (pbuh). The prophet of Islam (pbuh) says: “When Prophet Adam (pbuh) was still amongst water and clay [hadn’t been created yet], I was a prophet.” Similar to this hadith is another one that speaks of the chronological precedence of Imam Ali’s (as) imamate in relation to the creation of Adam (pbuh). There are countless other hadiths that disclose the same meaning with different phrasings.
4- Imam Ali (as) was without a doubt one of the signs of Allah's (swt) might and power and because of this, he is called “The Hand of Allah” (ید الله). He himself in a hadith says: “أَنَا عَیْنُ اللَّهِ وَ أَنَا یَدُ اللَّهِ وَ أَنَا جَنْبُ اللَّهِ وَ أَنَا بَابُ اللَّهِ” (I am the eye of Allah, the hand of Allah, the side of Allah, and the path to Allah).
Keeping all of the above in mind, if anyone believes that Prophet Adam (pbuh) was created by the hands of Imam Ali (as), it will mean that Allah (swt) created him through one of the manifestations of His power, meaning the light of Imam Ali (as) that was created from before, not that the physical body of Imam Ali (as) independently did such a thing.
On this basis, although the scale of belief in the matter you mentioned isn't as you put it, nevertheless, if anyone believes in it, it won't be in conflict with the accepted fundamentals of Islam, thus not causing those who might say so to be kafirs and mushriks.
At the same time, it can't be said that believing in Imam Ali (as) creating Prophet Adam (pbuh) with his own hands is something that can't be denied in the Shia school of thought, on the contrary, it can be questioned and researched about.
In the end, we would be grateful if you could send us the Arabic text of this hadith.
 Sad:75 “قالَ یا إِبْلیسُ ما مَنَعَکَ أَنْ تَسْجُدَ لِما خَلَقْتُ بِیَدَیَّ أَسْتَکْبَرْتَ أَمْ کُنْتَ مِنَ الْعالین”.
 Qisas:88 “کُلُّ شَیْءٍ هالِکٌ إِلاَّ وَجْهَه”.
 Ma’idah:64 بَلْ یَداهُ مَبْسُوطَتان ; Fath:10 “یَدُ اللَّهِ فَوْقَ أَیْدیهِم”
 Qalam:42 “یَوْمَ یُکْشَفُ عَنْ ساق”.
 Taha:39 “وَ لِتُصْنَعَ عَلى عَیْنی”
 Ale-Imran:181 “لَقَدْ سَمِعَ اللَّهُ قَوْلَ الَّذین”; Mujadalah:1.
 Ibrahim:32 “وَ سَخَّرَ لَکُمُ الْفُلْکَ”.
 Saffat:96 “وَ اللَّهُ خَلَقَکُمْ وَ ما تَعْمَلُون”
 Ahsa’i, Ibn Abi Jumhur, Awalil-La’ali, vol. 4, pg.121, hadith 200.
 Ibid, pg. 124, hadith 208 “کنت وصیا و آدم بین الماء و الطین”.
 Kuleini, Muhammad ibn Yaqub, Kafi, vol. 1, pg. 145, hadith 8.