According to accredited scholars like L.Brown, the bka’gyur is a collection of the translation of the pronouncements.
Are the bk’gyur the words of the Buddha transcribed?
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Bka’-’gyur, (Tibetan: “Translation of the Buddha-Word”), also spelled Bkaḥ-ḥgyur, Kagyur, Kan-gyur, or Kanjur, the collection of Tibetan Buddhist sacred literature representing the “Word of the Buddha”—as distinct from the Bstan-’gyur (“Translation of Teachings”), or collection of commentaries and miscellaneous works. This body of canonical literature contains more than 1,000 works, most of them originally written in Sanskrit and most translated (with great care) after the 8th century. They were gathered together in the 13th century, and the collection has been published in 100 volumes.
The Bka’-’gyur begins with a vinaya (“monastic discipline”) section, the only group of works having much in common with the Pāli literature of southern Buddhism. Then follow a few hundred sūtras, mostly of the various Mahāyāna schools but including a number of Sarvāstivāda (“Doctrine That All Is Real”) works, and several collections of avadānas (legends of “noble deeds”). Finally, there are several hundred Tantras, the special ritual and meditation texts of the Vajrayāna form of Buddhism characteristic of Tibet. These latter are divided into four groups, containing, respectively, worldly rites, religious rites, traditional yogic practices, and the esoteric forms of Tantric yoga.
You asked, "All perspective are well accepted if these scriptures are part of the canon" -- but the answer may depend on which canon (e.g. the Pali canon or the Mahayana canon).
I read a while ago on this site that the question of whether a text is "Buddhavacana" is a subject of debate or argument, disagreement, between schools.