There are 2 things to look at here:
1) Where POI gets the profiles folder from. Your best bet would be POI's docs or a POI user forum or support email. As a last resort, start a new
thread here with an appropriate subject to ask specifically about that. If POI give you a way to specify that explicitly, you can use that.
2) Where Java gets its temp directory from. If POI doesn't have anything else that it uses, it may either be using the java.io.tmpdir system property directly, or it may be using a java.io.File method that in turn uses the property. If POI is using the property directly, and doesn't have anything else that it will use instead, you'll just have to provide the -D arg every time. If it's using a File method, you're still probably out of luck, becsause I don't think there's any way to tell File to use a different directory.