This is actually for someone else and not me so I would run any title possibilities by him. He said he was 4 or 5 when he saw it (or part of it). That would be 1995 or 1996. It may have been seen in a small theater in NYC where it may have won an award. It could have been a short film. It may have been of a Latin origin. Second guesses of the origin were it being Canadian or European.
The aliens looked really realistic (not sure if CGI or not) and they pulled the pants off humans to determine their sex and put them on metal tables for examination/experimentation. The aliens he said made the weirdest facial expressions. There were humans lined up all along in the walls in these coffin-like structures with openings on their sides and they also had an organic lining in them that looked like skin but wasn’t. At one point a human loses their glasses.