If portable A/C units aren't sending the internal air outside, does that mean they're also just circulating outside air as a way to disperse the heat, rather than actually blowing air outside?
Some portable A/C units do send hot air outside, and some don't. The two-hose models AFAIK are the latter type (although the un-insulated hoses are wildly inefficient)
https://youtu.be/_-mBeYC2KGc