Hey Rashura,
Unfortunately there’s no utility for identifying/fixing corrupt assets. I’ve looked into that possibility myself, and ‘corrupt’ can refer to many different problems (which means that creating a tool to find/fix corrupt assets would take an enormous amount of time, which could be better spent fixing the cause of the corruption).
As for your situation, if the problem is your MyCharacter blueprint, I would recommend removing the blueprint from your project and then recreating it in 4.7 based on the 4.6.1 copy. If you converted your only 4.6.1 copy to 4.7, things get a little more complex. Trying to import the 4.7 version back to 4.6.1 is possible but often buggy.
To respond to your question about reference assets, I would recommend reading the documentation on redirectors: Asset Redirectors in Unreal Engine | Unreal Engine 5.1 Documentation
Using the FixupRedirects may clean up those errant reference assets you’re seeing in windows explorer.
Let me know if that helps,
Jonathan