Nokia 8.1 has a double channel LPDDR4X type of 4GB RAM.
Yes, Nokia 8.1 does have the HDR10 support and you can watch 4K videos on Nokia 8.1. You can record 4K videos also.
Yes, Nokia 8.1 does have the USB Type-C port.
Yes, Nokia 8.1 is a dual sim mobile phone.
Yes, Nokia 8.1 does support Qualcomm Quick Charge. It also comes with 18W fast charger.