tnHeb “In those days and at that time, oracle of the Lord, the iniquity [or guilt] of Israel will be sought but there will be none and the sins of Judah but they will not be found.” The passive construction “will be sought” raises the question of who is doing the seeking which is not really the main point. The translation has avoided this question by simply referring to the result which is the main point.
tnHeb “Oracle of the Lord.” In this case it is necessary to place this in the first person because this is already in a quote whose speaker is identified as the Lord (v. 18).