Already predicted by quite a lot of people and now they've been picked in EU LCS for the first time and look very broken tbh (especially Rakan with game deciding ults).
/edit To clarify: by Azir'd (or Ryze'd) I mean nerfing champions that are balanced in soloQ but end up broken in competitive, so that they get nerfed and end up being garbage in soloQ.
Neither of them are oppressive as of now so I don't see any major nerf any time soon. Maybe Xayah's E can get two more seconds of cooldown (early probably) if anything, but I don't think it's necessary.
Xayah is super strong in solo queue too, I don't know what you're talking about.
As some people have already pointed out, Rakan is mostly fine in solo queue, maybe even a bit underpowered. Xayah, in my opinion, could use a small nerf to her E though. They just seem oppressive because they're were played in a professional-level game by two players who could fully communicate with each other.
Neither are broken.
Azir was gutted after constantly popping up as the number 1 mid laner over and over again. Xayah and Rakan have barely been out for a month, and in fact; Rakan is getting buffs.
They won't, especially not Rakan. His kit is rather straightforward, there is no reason that he'd perform much better in organized play than in SoloQ.
Xayah needs set-up and proper feathers management, which can be tricky to fully exploit, so I could see a world where that happen, but I'm not convinced.
They're strong, but they don't look overloaded. I can see games where I'd rather pick, say 
over Xayah. The main reason why you'd want to pick them in pro-play is because they are stronger than a single champion when grouped together, but if the enemy picks one or bans one, they seems fairly basic on their own.
Rakan has to be doing some gamebreaking shit in order for that to happen as it stands in soloq he is worthless
