One of the challenges in translation is with idioms. Does the translator translate an idiom literally, or idiomatically, i.e. presenting what the idiom is thought to actually mean. Lets consider "children of wrath." According to the NET footnote, "children of wrath" is a Semitic idiom which may mean either “people characterized by wrath” or “people destined for wrath.” I am not sure what was meant by "characterized by wrath" but what I believe it refers to being altered by God's curse as a consequence of the Fall, i.e. all of us were made sinners. And of course, in the condition, separated from God, we are "destined for wrath" in the afterlife. And if a group of translators think the idiom means something else, i.e. "deserving of wrath," and they translate the phrase idiomatically, then more conservative students might see their effort as a mistranslation. I think the best way to handle idioms is to translate them literally, and footnote the possible idiomatic meaning. And if the version is a study bible, then the concordance might reference other places where the idiom is used, or where similar phrases are used, such as accursed children or vessels of wrath.