Working with XL screen size

Hey, 

I’ve been asked to prototype for a portrait 55 inch size screen, works out as 4572 px x 2572 px /1209.6mm x 680.5mm.  What size of frame should I be working with? Would it be ok to use 1080 px x1920 and the design would automatically increase to the size it needs to be? I am thinking about for user testing purposes. I would like users to test on the actual 55 inch screen by connecting it to the internet. I am worried that working in Figma with a bunch of frames the actual size would be too slow? Please help I’ve only ever prototyped for mobile and desktop sizes before.