1. Because CN ROM only has 2 languages - English and Chinese
2. Because other people think CN ROM cannot use Google so they decide to flash Global ROM
3. Because Fast Tech may not be aware that flashing to Global ROM will have issues with software update and can never go back to stock/original state. Bootloader will be unlocked forever and will have a warning message everytime you restart your phone.. this is forever. No turning back once you convert.

Ask seller on warranty part as it's warranty provided by local seller. Generally unlocked bootloader is void warranty for the official set unless you able to relock before send go service.

As per my understanding even after root also can receive ota update for official set. China set wise then no idea

Moto now is belong to lenovo. As this is unofficial China set, the warranty part after root is quite subjective depending in China side policy. No comment from me through, the best is ask seller if someone interested in the device.

I won't even consider import China set, who know how much they will charge if something go wrong after 1 year warranty to sending back to China without considering the part cost. I don't think seller will bear the cost and no way to repair it locally as official set counterpart is not even available.

Anyway the best is to check with seller. Lol but general rule of thumb before buying normally what also can be discussed, when problem arise then only we will know. That's why I rather deal direct with service centre instead of seller.

It really depends on luck, there must be some people buying import set without any problem. When problem arise just buy a new 1 very simple. For me I use device for more than 2 years normally so import set doesn't suite my need but it might suite some people.

Side story, I wish to join boat to pixel as software and community support is excellent. Hopefully it will be officially available in Malaysia in near future like our neighbouring country sing