More beef for Baker Mayfield ... this time the Browns superstar is getting into it with Arian Foster -- blasting the ex-NFL RB for being "too cool to show any personality."
It all went down on Twitter this weekend ... when a video of Baker dancing his face off caught Arian's attention.
"Your QB could never," the Cleveland Browns official account tweeted.
"*would never," Arian responded.
*would never https://t.co/XgHmkjFO0P— feeno (@ArianFoster) February 9, 2019
Mayfield saw the shade from the former Houston Texans superstar ... and went off.