Illaoi or Rek sai

Rek'sai has a great amount of utility in her kit. She doesn't appear to be super OP at the moment, but her mobility, CC, and farm speed could prove useful. I have not played her but I can see the value she would have.

You don't always have to pick someone based on current meta. One of my main champions is Mundo who is strong, but not an S tier pick in the current meta. I have a 62% WR over 40-ish games. ( Too lazy to look up my actual stats, you can if you're curious :D )

TL;DR I think Rek'sai would be the better pick between those two.

Illaoi is decent still, but I can't speak of how Rek'Sai is doing. In my opinion there are other champions you might want to look at first, but out of those two Illaoi is the top choice.

Then what champ do you recommend me in ranked then ?

Illaoi is complete trash right now. Ty Riot for nerfing an already weak toplaner.

Rek'Sai is fine but she isn't really a fighter anymore.

Kindred / Maokai.

Don't thank me.

Illaoi for a high damage, no mobility, team crushing tank. Rek'sai for a overloaded global Lee Sin easy mode.

i personally love Illaoi. shes a little awkward at 1st but she shits on most squishy top laners. learning the proper times for ulting and what not is key, also landing your e is pretty important too. Best part is Riot will probably buff her again soon.

You shouldn't buy either of those for ranked

Can't really speak for Illaoi, but Rek'Sai is pretty solid for the jungle, since she's not really "counterable"; junglers like her and Elise who have a lot of utility fit in most compositions, and it's not as if the enemy can shut you down by picking a certain jungler.

I will say that despite her straightforward kit, Rek'Sai is not that easy to master, and will take a lot of practice to use effectively. She is fun though, and has a very cool design.