However, there are places where none of those markers is present, yet at least some translations render the sentence as a question. The particular text brought out for consideration is Hosea 13:14. That verse reads as follows in the KJV:
I will ransom them from the power of the grave; I will redeem them from death: O death, I will be thy plagues; O grave, I will be thy destruction: repentance shall be hid from mine eyes. (Hos 13:14 KJV).
In the ESV it reads:
Shall I ransom them from the power of Sheol? Shall I redeem them from Death? O Death, where are your plagues? O Sheol, where is your sting? Compassion is hidden from my eyes. (Hos 13:14 ESV).
The easy difference to explain is the answer to the question, Why does the ESV have "where" at the same plac the KJV has "I will be"? The KJV translators read an infrequently used interrogative particle as the 1st person singular verb. This is one place where the Septuagint got it right, and the KJV translators should have paid attention to it.
But why does the ESV render the first part of the verse as questions, where the KJV renders it as statements? The problem is that there are no obvious markers of a question. The only real answer that can be given is this from Gesenius' Hebrew Grammar: "A question need not necessarily be introduced by a special interrogative pronoun or adverb. Frequently the natural emphasis upon the words is of itself sufficient to indicate an interrogative sentence as such." In other words, the translators of the ESV (and several other versions as well) seemed to think that the interrogative idea was obvious. Theological leanings on the part of the translators does not seem to play a role. Thus, the ESV, NLT, and NAS all render as questions. The NIV, TNIV, and CSB all render as statements.
Probably not a useful answer, but about as good a one as I can give.