Nope, you will have the market to yourself.
Just keep in mind that multiple people do screen upgrades and all kinds of special mods for the TurboExpress/PC Engine GT.
Also, PC Engine fans hardcore enough to play games on a portable using real hardware tend to have no interest in differently abled screen perspectives, as it defeats the whole point of authenticity.
They also tend to not be enthusiastic about destroying consoles to cobble together franken-systems. So any kit should ideally allow the console to be more or less restored. Also, the shell would have to be a very special design that is high quality and faithful to the PC Engine aesthetic, like the Super SD System 3.
Many thanks for your input on this.
1. Do you have links to people who do mods? I would love to check it out.
2. So screen must be 4:3 you mean? That was my idea as well.
3. I will only make something that is of high quality, there is no reason for me to half ass it as it is a niche product for a niche market. The idea of being able to restore it back to a normal working PC Engine is something I share as well, my idea was never to make a Analogue Nt version of a portable PC Engine.
A few questions for you if you have the time:
1. Could you tell me what mods, if any, are expected to be made for a portable PC Engine?
2. What screen size is preferable? Is there a minimum/maximum?
3. Weight wise what is the maximum for a enjoyable game time?
If you have anything else important to share please let me know.