That's not how it works, you have the device, you are the only one who could do the development necessary to add support for it. There is no budget for developers to go out and buy random gear on request, nor time or developer power for that. Either you get it working and provide a patch or (most likely) no one will.
Beyond that, it's not at all clear if this device would even theoretically supportable is unknown (but questionable) as well.
Thank you for your reply and clarification. I understand that there are no resources or budget to provide support for all devices, and I realize that this heavily depends on individual contributions.
I will try to study the device and see if it's possible to start working on it myself. If you have any advice or resources that could guide me through the initial steps of developing support for the device or adding a new patch, I would greatly appreciate it if you could share them.
By the way, many people in my country (Egypt) use this device and genuinely need the customized version, as it could solve a lot of issues, especially with networks and the limited features in the stock firmware.
The first step is documenting what SOC-, modem- and wireless chipsets are inside (and no, that doesn't magically get anyone to work on it) - at least I couldn't find information (nor downloadable OEM firmware images, which might already provide some hints) about it easily.
Only lantiq vr9 would be supportable, neither Broadcom, nor Mediatek - and I fear ZTE sometimes uses home-grown (unsupported) chipsets as well. Getting analogue phone ports supported is already unlikely, DECT is going to be impossible. So chances aren't great to begin with, even if you would find someone who owns the devices and wants to work on it.
I just heard about OpenWrt a week ago and was very excited to try it on my router (ZTE H188A). However, when I checked the supported devices page, I couldn’t find my router listed. I even tried searching for a router similar to my model, but unfortunately, I read on blogs that doing so could be very risky and might completely disable the router.
What I was looking for was simply to have additional features for my router because the stock firmware that came from the manufacturer lacks advanced features or proper customization. Some basic services, like QoS, don’t even work properly.
So, is there any alternative service similar to OpenWrt, or anything else I can do to gain more or better features for my router?