This is a concept for a one-off game.
In a hard SF setting, refugees from terraformed colony planets are being smuggled to Earth. The game takes place in the cargo hold of a spacecraft. The refugees are different offworlder races, who’ve been bred to cope with conditions on partially terraformed planets. For example a group from terraformed Mars who breath low-oxygen air could have pale skin, visible blue veins, and small air filters over their mouths or tubes runnning into their noses.
Any fairly large windowless room(s) could work for a venue, something like a storage room or bunker would probably be ideal. Dressed with lots of crates and barrels to divide up the space and give the feel of a cargo hold. Heavy sound effects of engine thrum. An intercom to the ship’s captain, who keeps them updated with their progress.
Most of the game would be personal interaction between the refugees.