Just no :T
None of them are really innocent they all have done or hid things. I personally don't believe innocence cam ever be obtained once you lose it. I know people are likely to comment about Mike's siblings and Mrs A so I will talk about them.
Evan is technically aiding Cassidy in killing people until they reach her killer, which makes him an accomplice to her and likely stalked people with her. There isn't much to say about him since we don't know whether he became like Cassidy, or not. Though Cassidy could've turned him against his father since he doesn't seem to remember much of his past.
Elizabeth game and book wise can be pointed out for many things. She somewhat can be blamed for killing Mike, and is the mastermind in Sister Location who's commanding the funtimes to knock out, hang, chase, and kill people, while PRETENDING to be a damsel in distress. She's 7,2 and weighs 585 lbs, that is way taller and bigger than Michael.
Michael seems to be shorter than Funtime Foxy. During her time before she became Scrap Baby I can only imagine how many people she likely killed along the way.
Book wise she mauled/nearly killed Carlton's dad, killed Aunt Jen filled with excitement as she ran down the hill, threatened Jessica because Jessica trash talked about William, broke into Jessica's house, kidnapped kids, aided her father, verbal abused, identity theft/impersonation, stalked people, assault, attempted murder, forced herself onto Carlton, domestic violence, and I'm pretty sure pushing someone to suicide is also a crime, a lot of them seem to be pointed at Charlie so Liz is committing hate crime as well.
Mrs. afton
There's not a lot to say about her but she is the most innocent compared to the rest. We don't have anything that says she's committed crimes or killed people. All her book representatives are seemingly the same way. I personally don't believe in her being Ballora since there's so little proof of it. At most Ballora is simply based and represents her.
If she was Ballora however Mike would be the most innocent. While she aids and kills people with the funtimes, even hanging people for display.
Compared to all three Afton kids Mike really is less guilty compared to both his father/both siblings, his only crimes being bullying and killing his brother. There's nowhere that shows he killed anyone else or was aiding his dad. As he confirmed that he was coming for him.
Freddy files confirming his goal was freeing the kids/spirits, it can be debated that he's trying to make up, and atone for what he did to Evan even going to the extent of suffering, and dying in the process.