Thanks for the info. The OpenWrt mt76 driver wiki page has a link to Mediatek website listing this feed, so I suppose it's known to many. I imagine pesa1234's custom build & many of its fork on Github are also using patches from Mediatek Git repo.
Upon a more detail look though, I cannot find mentioning of using any close source drivers from these projects that the OP specifically mentioned. Maybe Mediatek has moved some functionality to binary firmware file (well, that is what NVIDIA did (see last paragraph) when announcing their 'open source' GPU driver) , or maybe I have missed it somewhere?
If you happen to find any MT6000 project mentioning of adapting close source binary driver files to work with latest Kernel, then I am interested to learn about it.