His addiction is beating high scores and achievement unlocking for virtually every game he plays on ipad or PC.I suggest you look into 2xe resources. This sounds like my oldest child, until we figured out how to get him adequate accommodation. A child who is both gifted and has challenges is often enormously frustrated. They tend to go for the only thing that works to get them some relief from the boredom of a bright mind trapped behind barriers and treated like they are dumb.
I also will recommend that instead of trying to find him a non-language outlet that you focus on helping him overcome his receptive and expressive disorders enough to adequately connect with the world around him. This was the approach I took.
I addressed individual pieces of the puzzle. I got him to learn to talk through things. I taught grammar, vocabulary, typing, and all the different pieces of how to write separately. We homeschooled for a long time and the first five years, he was incredibly resistant to writing anything. I did as much as possible without requiring him to actually write (other than working some on his handwriting). Then he discovered FanFiction.net and wrote several thousand words the first few days.
It is important for the child to be interested. That is the motive. But a 2xe child also needs help overcoming a lot of different barriers.
I have sympathy for what you want to do here and why, but I think you have a lot different things backwards.
My son has a tremendous interest in video games. He blogs about it and he has taken up modding games, but it has taken a long time to get here. I know a little html and css and I was able to explain coding to him in a way that made sense to him. He already knew a little html because of some forum he participated in. When they changed what was available, he kept using the font colors and other effects he liked because he had memorized the code. He didn't yet understand that was "coding."
I don't remember the discussion he and I had about all that, but I do remember it was a big deal to him.
There are lots of things that can help kids like this. You haven't really given the kind of information that would allow me to tell you specific things you could try. But, generally, you want to try to help him overcome his weaknesses enough such that they don't prevent him from doing what he wants, help him finds ways to get around things he just can't do (because they often aren't actually pertinent anyway) and support his interests.
I found it really helpful to do personality profiles and learn about learning styles. Instead of treating my son as a handicapped child who couldn't do "normal" things, I treated him as an interesting, quirky kid who needed a custom fit approach. I think this generally works better and gets better results. I also think it is a more accurate concept for people who are different.
If you haven't heard of Temple Grandin, I suggest you google her and start reading books and articles by/about her. She is autistic and also very accomplished. Another good resource is the book "Children with Emerald Eyes."