Calling Wesley "racist" was a bit tongue-in-cheek. But it just comes across as odd to me that he would see a Benzite step off the transporter pad, someone who he was just told
was not a new officer but part of the exchange program and immediately assume that he's his friend simply because they happen to be of the same species.
They had different names and, honestly, it never even dawned on me that it was the same actor. Hell, I think the two had somewhat different personalities.
I think any confusion for the audience could have been better cleared up than having Wesley pretty much wondering how Benzites can tell one another apart. Mendon should have responded with, "How do you humans tell one another apart? You all look alike to me