@Axeofdoom
I have no doubt she is probably cheating on you via IMVU. Personally, I would not mind if my wife got off on some poor looser cucks' pixel dick that's probably over 1000 miles away while I'm pounding her cunt guts deep inside out IRL. That's my marriage though. If her activities bother you that much and she knows you would not like it, then it is cheating.
Are you married IRL and living together? Got kids together yet?
Planning to divorce if you do find proof?
If so, I would recommend against throwing this investigation of yours and its findings in your wife's face. Spying on your spouse's online activities, even if you think she is cheating, is illegal. She can use it against you in court during the divorce.
Instead of telling her about your findings, I would save the evidence and give it to your lawyer. Your lawyer will know how to sopena legal copies of her activities from the phone company. Otherwise, any evidence you supply could be found admissible due to being illegally obtained ... on top of charges of illegally obtaining her data.
For your personal investigation, it sounds like you looked at her rooms. She went into sex rooms with sex poses ... there's no reason to go into those if you're not planning on having sex. As others have said, if she has nude outfits ... the only reason to have those is to have sex or strip. What more proof are you really looking for? You've already proven it. Any further details from the sounds of it, will only serve to hurt your feelings.
If you're not planning on divorcing her, I'd recommend you either reconsider or accept her cheating. Your relationship sounds toxic. Distrust is a poison raging through your veins. You will not live a long nor happy life till you either accept your wife and her repeated cheating, or get rid of her.