Beyoncé Producer Killah B Teases Possible Country Collab with Taylor Swift

Beyoncé's keeping the surprises coming with her dive into country music -- that's according to Killah B, who produced and co-wrote her new track, "Texas Hold 'Em," and hints something huge is on the horizon. We spoke to the Grammy-nominated producer Tuesday on "TMZ Live" ... asking him if Bey's upcoming "Renaissance Act II" album would feature any guest collabs, particularly with her good pal Taylor Swift, who…