Russell Westbrook -- Fashion 'Imitator, Not Originator' ... Says Style Expert

Russell Westbrook has a new clothing line -- which includes sheer tops for dudes -- and while that might sound groundbreaking ... one fashion guru says it won't earn Russell respect in the design world.

Robert Verdi of TLC's "Brides Gone Styled" joined us on TMZ Hollywood Sports ... for a brutally honest opinion of arguably the NBA's most stylish baller.

Verdi gives Russell credit for how HE dresses -- it's what he makes for everyone else that needs some work. Check out the clip, and the guy nips.