Which also were accounted giants - This is not a fortunate version. The word is not giants, but רפאים Rephaim, the name of a people. It appears that the Emim, the Anakim, and the Rephaim, were probably the same people, called by different names in the different countries where they dwelt; for they appear originally to have been a kind of wandering free-booters, who lived by plunder. (See on Deuteronomy 2:10 (note)). It must be granted, however, that there were several men of this race of extraordinary stature. And hence all gigantic men have been called Rephaim. (See on Genesis 6:4 (note), and Genesis 14:5 (note)). But we well know that fear and public report have often added whole cubits to men's height. It was under this influence that the spies acted, when they brought the disheartening report mentioned Numbers 13:33.

Which also were accounted giants, as the Anakims,.... Because of their bulky size and tall stature; or,"the Rephaim were they accounted, even they as the Anakims;''they were reckoned Rephaim, a name for giants in early times, even as the Anakims were; see Genesis 14:5.
but the Moabites called them Emims; to distinguish them from the Rephaim; so that it seems this name of Emims was not originally their name, but they are called so by a prolepsis, or anticipation, in Genesis 14:5 since they had it from the Moabites, a people of a later date.