Would a low end Turing GPU be better Vs a High end Volta GPU for plex transcoding?

Hey all i have these 2 gpus doing nothing

and a friend is wanting a Plex machine to be able to do 4x 4k streams at the same time around his house and happily would help he build a machine out of my old and unused parts, I currently have a Titan V and a NVIDIA T400 doing nothing and was wondering as the T400 has a newer architecture and apparently has a better NVENC engine, would this mean its better for plex than the older Volta card?

I am going to go out on a limb here and say, yes? There is nothing else that the other card brings to the table if you are only encoding and decoding streams. The video codec pipeline is not the same as the graphics pipeline as the NVENC hardware is basically a co-processor (simplification) to specifically handle video encode and decode.