Reading the relevant paragraph in the documentation about Roon’s Import Settings (linked below) might help too:
Do it before you add the albums to Roon. I personally think that using the IMPORTDATE file tag is the best solution to do what you want. Make sure to provide a complete timestamp (date and time) value and not a date only to be on the save side and prevent any misinterpretation because of time zone calculations. If you have a metadata editor that allows for batch edits or editing many files at once then you should be good to go. Some thoughts about file tag tools can be found in the following thread: