Ever since this question was first asked I've been looking on and off for some information on it. As far as I know as Caelistis' answer states there has been nothing on it. Again as their answer states this is most likely just an Easter Egg to the group. One of the founding members of the group was Doctor Strange who had an origin film coming out the year after so again it could be an Easter Egg/teaser to that for eagle eyed fans like yourself.
However, to take this a step further Kevin Feige was asked about introducing the group to the MCU in a press conference for Doctor Strange. Whilst he doesn't say it will happen or not, he does say some members of the group will interact in upcoming films. Of course now we know that was them all interacting in Avengers: Infinity War and Avengers: Endgame to beat Thanos and all become Avengers.
Well, what's fun about the Illuminati is that there are certain characters interacting with other certain characters, so I don't know about that particular storyline, but certainly some of those characters you will see on screen in the next Avengers.
Screen Rant, Kevin Feige Says Avengers: Infinity War Features Illuminati Characters
After the events of Avengers: Endgame we can probably rule out the Illuminati existing as they do in the comics but that doesn't mean the group won't form later down the line with different characters. It also doesn't rule out a secret society that just hasn't been shown yet that will come to light in the future but it does seem unlikely.
