First I would not move AppData over because it is always a prime suspect for what may have corrupted the account. Instead if you have games or an app that needs that Appdata to continue without disruption of your progress or needed data, just move it alone. Here is how it should work:
When you browse from the new Admin account to C:\Users into the new account, it will pause to issue permissions to all the data, with a green progress bar that runs across the URL box and may take some time depending on how much data there is. Once the User folders open, I would open each one, from Hub (three dots) button choose Select All, right click group to choose Copy icon (or More Options > Copy), then browse to the new Account corresponding folder to right click on empty area and choose Paste.
To copy out certain AppData, on the User account folder choose View > Show > check Hidden Files and Show Check boxes. Browse into the data you want to select, check it's box or Right click to Copy, move to corresponding folder in new account and choose Paste.
It may be necessary to Take Ownership of some more restricted AppData. Use this handy right click shortcut which installs a Take Ownership shortcut to your right click menu to use in cases like this on files and folders which won't cooperate: https://www.elevenforum.com/t/add-take-ownershi...
You may need to use it on all parent and child folders in the path.
The only warning is to not use it on C:\Windows folder files as this will compromise security.
Keep me posted on your progress as I will be here to help until the case is resolved.
_________________________
Linked tutorial is from a trusted Microsoft MVP