Now, I'm wondering about those people called Nephilim, or giants/sons of God in Gen 6.
Is it possible they were around prior to that time chapter? Taking a wild and possibly wrong guess.
There's nothing wild about your guesses, so I think there's much value in your question. Personally, I would say that the way Genesis puts the narrative in chapter 6 about the Nephilim
could suggest indeed that there were some beings closely identified as human in one form or another. Especially verse 4 -
There were giants in the earth
in those days;
and also after that,
when the sons of God came in unto the daughters of men, and they
bare children to them, the same became mighty men which were of old,
men of renown.
There seems to be a delineation between two periods here:
(a) in those days
(b) and also after that
The question that immediately comes to mind is this:
where and
when did the giants emerge? Surely, that verse did not say that they giants were the
products of angels having sired human children from women - no, for that is the
traditional way many people have read it.
Looking carefully, the verse first notes that there were giants
in those days and after that. . Certainly, after the angels came down to do their 'thing' with those women, we read the product was some species which
became "mighty men" (distinct from the "giants" in the earlier part of the verse).
Now, if this line of reasoning has some substance, I dare say that the giants were already there before the angels sired children through women. The necessary question would lead to the inference that some beings closely in semblance to humans were already on the scene - how far back or when exactly they appeared is not something I can decipher from Genesis at the moment.