Yes, Samsung Galaxy A70 has a dual 4G sim slot. You can use 2 4G sim cards at the same time.
Yes, Samsung Galaxy A70 does have NFC support.
Yes, Samsung Galaxy A70 does have a USB Type-C port.
Yes, Samsung Galaxy A70 does have fast charging support. It supports 25W of fast charging. The fast charger is also supplied in side the box.
No. Samsung Galaxy A70 has 2 dedicated slots for sim cards and a dedicated MicroSD card slot. Basically, one will be able to use 2 sim cards and a memory card at any time.