I don't remember Riot giving any info about Eve's update except telling us that she could use one. Mainly because it's ways off and probably not the worst offender.
I personally think that Stealth System should be looked at first. Considering that stealth champions are a few and far between and that the ones we do have it all have some sort of a different mechanic that needs to be balanced per champion basis, it's very restrictive and won't probably find a way on new kits + add another level of complexity to the game of how to deal with another stealth champion, rather then how to deal with stealth.
Also about Eve, I used to main her but the changes to Magus and her getting nerfed constantly just turned me off.
For what i have gathered, she is supposed to be an assassin or a fighter but her pattern of play doesn't give her kit a lot of burst in the kit (maybe nuke E and constant Q spam) and relies heavily on surprising the enemy to deal that damage..
Outside of the escapes and no flat damage R, she doesn't have much going for her.
I haven't tried her out after the new season started (where Thunderlords and Runic Echos roam free) and i can't help but wonder if the early game winning prerequisite can help her or not.
She can help and win the early game but if her team is losing, she can't do anything.
IMHO, she could use a new model (Riot did tell us this) and maybe freshening up her skills.
A part of an future update (like Juggernaughts, Marksmen and future Mages - she isn't a part of the mage update) but honestly, i don't feel like her assassin-y pattern is healthy for the game or delivers her fantasy.
The only thing i like about her kit is perma stealth. That's the only thing i find unique about her that should be kept. And a full new kit build around that passive.
P.S.
That's what i'd like to see anyway, this is just a discussion, Riot did not announce anything except that her model may be outdated.