Traditionally, imaging for photo/video is RGB or decimal. There is no hex input in Vegas, but there are many small utilities and online converters to do the work for you. The standard Windows color picker shows Hex, Rgb, Lab, Hsl, and cmyk as well, I believe.
May issue is that my favorite color palette generators use HEX Code, There are of course RGB/CMYK numbers, but the pdfs I get also lists different shades of said colors that are listed in HEX Code
VEGAS EFFECT/Hitfilm has it. So at least thats there.