Yes...they are much different. Especially passages that can be tweaked to appear to be christological, when in the Hebrew text it is nothing of the sort.
As you may know or not, only the first 5 books of Moses was translated into the Greek by the Rabbi's. The authorship of the rest is unknown.
The current Hebrew bible is based upon the Masoretic text and not the septuagint. Furthermore, the main problem stems from English translations, where the Hebrew translations, tenses and contexts are all deviously changed to render a christological meaning in many passages.
I would be happy to supply a list if you would like.
The King James Bible was translated from the Masoretic text.
It’s the Catholic’s Bible that was translated from Septuagint.