The problem is not a separate creation in chapters one and two. The split between Adam and Eve was the evolution of humanity. Eve did not happen on day six. In fact there was a 1000 year period of perfection without death before Eve was evolved in a single process.
The ramification is that on day six God created humanity that contained both genders. There was not even a biological function. Humans actually multiplied. It was not a combination of biological sperm and eggs. No death or mutation period. When a son of God multiplied out of necessity, it happened. Male and female traits were contained in and passed on with no changes for 1000 years. Necessity was determined by the economy to actually prevent death from occurring.
What sustained this economy? Genesis 1:29-30
29 Then God said, “Here! Throughout the whole earth I am giving you as food every seed-bearing plant and every tree with seed-bearing fruit.
30 And to every wild animal, bird in the air and creature crawling on the earth, in which there is a living soul, I am giving as food every kind of green plant.” And that is how it was.
Wrong interpretation: the plants and trees themselves. Nope, that is and would be death and destruction.
Truth: The fruit and seeds themselves. On day 3 God placed every every plant and tree into the ground. No seeds springing up. The whole earth was planted with the oxygen giving, seed and fruit producing plant and tree life covering the whole earth. All that would be done is the production of seeds and fruit. On day 5 was the creation of birds and fish. The birds ate seeds and fruit, and the fish cleaned up the waste. On day six all animal life and sons of God were created. The sons of God were in charge and the whole earth had an economy with only seeds and fruit as a commodity, and the fish cleaned up the waste. No seeds nor fruit died in the process of producing more plants and trees. It would mess up the perfect balance.
That is why chapter 2 verses 4-6 could never make sense. It is not creation out of order. It is the generations of the earth without death, and not a single seed died in the earth for 1000 years.
4 Here is the history of the heavens and the earth when they were created. On the day when Adonai , God, made earth and heaven,
5 there was as yet no wild bush on the earth, and no wild plant had as yet sprung up; for Adonai , God, had not caused it to rain on the earth, and there was no one to cultivate the ground.
6 Rather, a mist went up from the earth which watered the entire surface of the ground.
It was not just because humans did not till the ground. It was true they did not have to. Even in nature, there was no seed or fruit allowed to die, in the ground, for 1000 years. It was called a Lord’s Day. God did not create nor change, nor allowed change to happen relating to death. Yes, the sons of God seemingly had to multiply rather quickly to gather up all the seeds and pick the fruit, and the birds and animals all helped in the process of running an economy that no seeds or fruit died but sustained life on earth. Animals and the sons of God would have been evenly spread across the face of the earth.
Now after 1000 years enter God. He planted Paradise the Garden and separated His chosen son of God, into a walled area, that would be home (eventually) to billions of this one son of God’s living space. He brought all the animals this particular son of God would need. God then had this individual call all the animals what this individual thought proper. Then God called this son of God, Adam. Then God did the next step and created a biological male and female. Then time started for Adam. 30 years later, Adam disobeyed. 100 years after that, Seth was born.
History of fallen humanity began. Cain and Abel were born in the Garden before the fall. Chapter 4 is their history separate from the other 3 chapters. They were perfect biological sons of God in the process of a separate male and female form. At the fall, Eve was changed biologically and birth would be forever changed. Cain was the only biological offspring of Adam with a full image of God, and he was male. We do not know if the sons of God were biologically forced to have genders or not. We do see that starting with Methusala, who had daughters before sons, that those daughters started a process of different types of mutations involving humans that would decay and eventually die with the sons of God.
For 1500 years, and the point death was certain, the sons of God now with the ability to kill and destroy, drastically changed the face of the earth, because they were actually God on earth. And no longer bound by God’s will. In fact that is why God finally declared, “His Spirit, the God part, would not always strive against them and their spirit.” Adam lost his connection with God at the fall. That is why he was cursed by God from even having offspring for 100 years. Seth also had to wait 105 years himself. That time frame kept dropping. This is the record that God left us in Genesis, in the first 4 chapters.