Camille/Fiora both have multiple AA resets, a lot of situation true damage tied to a minigame, both are high mobility, both create some kind of zone and both . Hell, Riot has straight up said Camille's ult was something they thought about for Fiora's rework.
Kled has a weird situational knockup/slow (Sion, Riven), a passive with an AS steroid, a shittier Renekton E and a Sion ult that's better at some things and worse than others, off Skaarl Q is mini Graves ult. Also Skaarl is a reskined revive passive tied to a rage bar. It's the illusion of being unique.
Ivern and Nunu are both junglers who cannot carry a game themselves that rely on supporting their team to win, with good counterjungling. The difference is that Ivern has multiple support tools due to being designed as such and being a modern champion, while Nunu has multiple soft peel options and an MS/AS steroid.
Jhin Q/Passive and Varus W are the only things that aren't somewhere else on the others kit. Jhin W = Varus Ult, Jhin E = Varus E, Jhin Ult = Varus Q and you play them both exactly the same; wait until you've landed enough poke or snare then let your team follow up.