Holy moly, cant believe i havent stumbled on this piece of software/plugin before.
I seriously recommend downloading voukoder 5 along with its vegas pro plugin, it works just like any other render preset.
The thing is, due to vegas pro nvenc rendering stopping every other second (because the buffer limit is in vegas somehow extremely small) the speed of voukoder 5 is ridiculously fast compared to vegas pro native gpu rendering...
15 minutes of h265 footage took a whopping 3 minutes to re encode!
Also the best thing.. its free.
So yeah, if anyone else is getting frustrated with native gpu rendering stopping every second and then rendering 50 frames and doing the same thing again, i suggest trying this one out!