I have the same issue. I noticed that if I leave it on long enough, the blinking stops. It’s annoying though. Still waiting for the seller I bought from on Ali Express to respond.
I noticed it more when I was using an app called Lux to reduce the minimum screen brightness in android. It’s like the screen refresh rate is too slow in android. I think it will be rom related so will have to wait for Chuwi to fix or a custom rom.