A twist on the clone proving itself thing I once encountered in a gamebook (like Choose Your Own Adventure but with stats, an inventory and occasional dice rolls) was that you got cloned, and had to compete with your clones to prove you were the original. If you failed, you fell on the conclusion that you were a clone all along with the memories of the original, admitted defeat and were effectively left to die.
I loved the sense of self-deprecating gloom, but I've never encountered it anywhere else. It was in a Sonic the Hedgehog gamebook named Metal City Mayhem.
Back on topic, my apologies.
#1 is called Spot The Imposter.
#2 is also known on TV Tropes as an Adrenaline Makeover. The best-known example I could think of was Violet in The Incredibles... I basically went to that work's page and hit Ctrl+F for that one.
#3 I have no earthly clue. Yet.
#4, as Mercen-X points out, is the words matching the hornplay. Effectively that makes it a With Lyrics scene, in that there's instrumental music but lyrics are established. That's as close as I can get.
On that note, if you're looking for trope names, go to a work where the idea you're thinking of is exemplified and check what name it comes next to, then read its trope description and see if it's accurate enough. 'S what I do normally. Can't think of an example for that inspiration paradox one you mentioned, but if you can, go try that approach. That's bound to find you your #3.
P.S. The proper word is "Tropese" pal, not Trope-talk. Watch out though, TV Tropes Will Ruin Your Vocabulary