To demonstrate that translation makes inspiration then we go to the Bible as the Final written authority. When Paul quoted partially the Book of Psalms 2:7 as recorded in Acts 13:33 which was written originally written in Hebrew and possibly spoke that in Koine Greek when Paul went to Antioch of Pisidia before the Jews. While I may have assumed he quoted those Hebrew text and spoken into a Greek (translation) but the undeniable thing is that St. Luke wrote the original Hebrew into a Koine Greek is really a translation and the Heb translated in the Gk gets its inspiration. So that was a very basic example why translation preserves the inspiration.
Another, is the copies of the scriptures constitute inspiration. Paul to Timothy is explaining that the copy of scriptures (not the original one) held by Timothy “is given by inspiration” so copies preserves the inspiration.
Translators are not inspired; the scripture is. The so called “originals” either written in parchment (vellum) or in papyrus (scroll) where Paul, Tertius, and other Apostles originally wrote them were no longer with us. This without a doubt were inspired scriptures. Soon these autographs were copied and copied and faithful copies does preserves the inspiration while there are other forces that are work behind the scriptures and wanted to mutilate, change or corrupt the word of God as Paul and other Apostles had warned of these things does not preserves the inspiration. Now, we have to take note that these copies either faithfully done or not were both came from the same origin and these were translated we called Versions.
No it was not in anyone’s decision that translations preserve inspiration but that is what the Bible says. God demonstrated preservation either by copies or by translation. The Holy Spirit the author of the scripture confuses no one. I think it is proper to say that it’s about accurate translation without losing the purity, hence, it is not mixed or corrupted. Once the translation lacks accuracy, then loses it purity.
The paraphrase or free translation, the dynamic equivalency/ impact translation, the literal does not carry the words, the sense, the style and the emphasis of the Heb-Ara-Gk and may not set in a proper of the English language. The need of Formal Translation is the best way of translation as in the KJV text. What about the other Modern English translation? Since inspiration refers to the whole not in parts then it is not considered ‘given by inspiration’ though we have some theories of inspirations, either partial, thought or dynamic. What I believe is what the scripture teaches “All scripture is given by inspiration of God” and I take the KJV English text as scripture. If other translations say they are the same as the KJV, then it must be proven “Prove all things, hold fast to that which is good”.
Of course my belief about the KJV is to be accepted or not but I wouldn't enforce it to anyone in here, rather let God speaks.