I need some tips for playing Eve in URF

So I'd like to think I'm pretty good at playing Evelynn. I have thousands of normal games played with her as my main. My highest URF score was 49-0. I had a 90% winrate with her in URF for a while, but I've slowly sunk down to 70%. Now that I'm being matched against plat and diamond players every match, I just can't keep up. Everyone does more damage than me or they have permanent stunlocks or infinite mobility. I got wrecked by an Eve that used gunblade, but I haven't been able to use it to much success myself.