DK Metcalf learned sign language to trash talk to opponents

The NFL has tried to crack down on taunting in recent years, but Seattle Seahawks star receiver DK Metcalf appears to have found a loophole.

During an appearance on “The Rich Eisen Show” last month, Metcalf made the hilarious revelation that he learned American Sign Language so he could

“I kept getting flagged for my mouthing, so, I gotta sign my s—talking now,” Metcalf…