Other than opening individual questions, is there a way to find responses that have been tagged as offensive?
I am not aware of any filter acting on the flags. You can filter on tags but flags aren’t tags.
In this case I should fess up here. Today I closed a window on my computer but nothing happened so I did what any computer user does, I clicked again. At that exact time the window closed and my click changed the offensive flag on the question in the window below, I immediately changed it back but was embarrassed to see that I had received a badge “Citizen Patrol”.
Sorry, Al
Don’t be sorry for the badge. It only means you used a new feature for the first time. Your learn by mistakes 
Interesting, the “flag offensive” change doesn’t even seem to show up on the activity tab in the user profile. You learn something new every day.
If only I did learn from my mistakes. I’ve been pressing the mouse button harder a second time since before windows 95; if I’m lucky nothing bad happens.