Unrivalled is an FPS Escape-from-Tarkov-like shooter that's already been in development by a team of about 20 passionate people since January. You can find out more about the game and even play the
alpha build to check out the weapons and movement mechanics, which have improved a lot, though.
Your role as a Material Artist will be to create seamless materials to integrate into our environments. You'll be given references and instructions. I myself am familiar with Substance Designer, but whichever software you use is fine as long as the results are good. No payment now or ever, other than your name in the credits. If you're interested, DM me your portfolio. Cheers!