Luhal moves out, and while the orc is surprised, puts his scimitar in position to threaten a deadly strike. Then he uses a Free Action to speak (hoping the orc understands the local goblin lingo), ordering the orc to hold still.
The intimidation factor would not, then, be a matter of posturing and puffing up. Luhal doesn't do empty posturing. The intimidation would be a matter of "I am threatening, very credibly, to kill you unless you do what I say." The reality of danger hopfully forcing itself on the orc's awareness, rather than the appearance of danger hoping to impress the orc.