I really love both of these champs myself and find im only proficient at both. Honestly I can't really say I know anybody who fits the niche as good as these two.
Twisted Fate's one of the only mages in the game who has lane matchups where he either has the potential to survive it or gets utterly stomped. No winning, but can still become insanely useful with his kit. I don't know any other champ that has issues like that
Shaco's one of the few(maybe only) junglers in the game where you actually NEED to figure out what your opponent is doing.
Is he starting krugs/gromp?
Does he have wards?
When should I invade?
Will I be able to get this kill?
Which lane is he headed to?
Knowing this stuff is far more crucial for Shaco than most other junglers
You need to always be a step ahead of your enemy with Shaco to get him to work. Otherwise you will be horribly outplayed. He's also one of the few assassins who feels like an assassin to play.
Again, im not really sure any other champ can be compared to these two specific champs in any way. They're one of the few unique champs in the game that's not overloaded as fuck.