Albert Teichner 
World in a Mirror [EPUB ebook] 

The delegation landing on the planet Newtane was welcomed by a handsome race of people that were almost as human as they were. Except somethings were backwards. Their expressions were opposite. A frown meant happiness and a smile was a sign of displeasure. Their hands were backward with the thumb where the pinkie should be — and they were all left handed. When a savory feast was presented to them, the delegation opted for their synthetic (and safe) food, except for Hacker. The young, reckless man signaled a request for meat. In a world so opposite is smelled so much the same. What could go wrong?

This Science Fiction Classic was written by Albert Teacher  and first appeared in the Worlds of If Science Fiction magazine in September 1962.