I still have my old Hotmail address as my primary alias, but I don't use it as my primary address. I created a new alias that I use for main correspondence and slowly I've updated my contacts to use my Outlook.com address. When I made the new alias, I didn't configure it to move all email sent to that address to a specific folder, I had it configured to drop to the Inbox. Then I created a new rule that moved anything sent to my Hotmail address to a new folder, as if it was actually an additional alias. When you create a new alias, usually Outlook.com will create a specific folder for that and then it will create a rule to send anything sent to that address into the corresponding folder.

This works flawlessly except for one thing: calendar invitations are still sent through the primary alias even though I've configured it to use the alias I want. It's a bug that's been reported, but just beware. I haven't changed my primary alias, I just move the mail to a specific folder that never syncs to anything and I rarely every check it. I plan on enforcing a rule to delete all mail that is sent to that address so I don't ever get SPAM anymore. That Hotmail address is at least eight years old and it get's LOADS of spam.