Seems similar enough to some existing routers that support may be possible?
Spec - 1. MT7981A+MT7976DA+MT7531AE, three chips solution, stable performance.
2. Support 802.11ax(WiFi6), 802.11ac(WiFi5), b/g/n(WiFi4).
3. Support 2.4GHz&5.8GHz dual band, signal is more stable, efficient anti-interference; 3000Mbps high-speed transmission rate, better Internet experience.
4. Euipped with 1*10/100/1000M RJ45 Ethernet WAN port; 4*10/100/1000M RJ45 Ethernet LAN port, Full gigabit network port, wired transmission is smoother.
If you can't find information and a dedicated firmware image for your exact device (down to the hardware revision), then the device in question isn't supported. Based on your description, it may be supportable - but that still means $someone has to do the actual development to get it supported. If in doubt, this $someone will be either you, yourself - or (more likely) no one. Just that it's possible, doesn't mean anyone (else) will buy this device and do the necessary porting. (While I can't open your exact link (geoloc), ~140 EUR for an 128/256 AX1800 device doesn't sound particularly convincing, the flint2 is cheaper and better, as well as locally available, but maybe you see a different price in your region).
Read this as, "don't bet on potential future device support", unless you know what you're doing and are willing to do the necessary development yourself. Always restrict your search to known-supported devices that already work right now and for which all the little warts and kinks are documented already.
I’ve found this Git page, but I am not knowlegdebale enough to build an image from this info. According to the page, it is supported, but I can’t find a pre-built image…