Is that within Revit EULA to use programs like sandboxie? New versions of Revit won't allow you to run multiple local copies of the same central model on a single machine, however in some situations this can be really useful. For example prior to revit 2025 UI was blocked entirely while exporting PDF sheets, which could take a very long time. In this case you might want to open the model in a second instance dedicated only to exporting.
While this could be accomplished by detaching the model, it can take a long time if central model is hosted on BIM 360.
Therefore, I'm wondering if one could use sandboxie to isolate Revit processes and make it open multiple local copies of the same central model on one machine. I am not sure though if this would raise any flags on the Autodesk licensing side?