Regarding the gun issue, you've said more than once that a person only has to feel threatened by another person with a gun no matter what the person with the gun says his intentions are. I may not have your exact wording right but that is the gist of it. I don't think that Mcmichael said that he ever intended to shoot Arbery with his gun.
Regarding criminal trespass, if I accidentally leave my door unlocked and come home to find some stranger chilling out on my sofa and if I pull a gun on him because he is in my house without permission, does the stranger have a right to shoot me with his gun in self defense?
The exact wording is: "Commits an act which places another in reasonable apprehension of immediately receiving a violent injury". It does include the word "reasonable". If someone is toting a gun from a truck beside the road into the woods to hunt turkey, that would not cause a "reasonable apprehension" of injury. If someone has been chasing a person and yelling at that person, and then produces a gun that would cause a "reasonable apprehension" of injury. If I am with another person and that person shows me his gun and describes the details of that gun, that would not cause a "reasonable apprehension" of injury. If that person and I are arguing strongly and he then pulls the gun out and holds it in his hands, that would cause a "reasonable apprehension" of injury.
Intention doesn't matter with respect to assault. What do you think McMichael's intention with the gun were? He had been chasing Arbery and trying to detain him. This is pure speculation on my part, but he likely thought that the gun would force Arbery to stop, so he could be detained. Why would the gun force Arbery to stop? It would only cause him to stop if he thought there was a chance of being injured by McMichael.
Many people seem to think that if "they" are in control of a situation, that causing fear in others is OK. Many high school and college kids will play pranks and try to scare someone into thinking they are being mugged or attacked. My thoughts, even at that age, were that if I am attacked, I will respond with as much force as I can deliver. If someone had played such a prank on me, it is highly likely that before I was able to understand that it was a prank, people would have been shot, stabbed, clubbed, or impaled with whatever I could get my hands on. Frankly, even though it would have been a prank on the other party's part, I would have been justified in my actions because they caused me to fear for my safety. (Now that I have a family, if I am with them I would react more calmly trying to minimize injury to my family instead of immediately trying to take away the ability of the other party to injure me.)
If someone is in your house, you arrive at home, and they shoot you, they are going to have a very hard time convincing the police or a jury that they only shot you because you entered the house and pulled a gun on them. Once again I am not an attorney. I would think that there are a lot of other things that would come into play in that situation. If you ask them to leave, they would be committing trespass at that point. If they do ANYTHING other than quietly leave after you ask them to, it would be very easy to argue that you had a "reasonable apprehension" of receiving an injury, at which point you can defend yourself. Your question is much more complicated than "did that person violate the Georgia trespass statute?"
You seem to believe that I am arguing that it is morally and socially acceptable to enter property without the owner's permission. I am not. I don't even open the door and enter my parents' house. I knock on the door and let them open it. I am simply describing the trespass statute. If you don't damage property, enter after receiving notice from the owner, or don't leave after being requested to by the owner, then you haven't committed trespass.