I would appreciate any insight on the subject. Thank you!
4 answers
You should be able to do this natively without triggers. Depending on how you use the Case Origin picklist today, you can add values to that picklist for the different "To" routing addresses, so each of the routing addresses get a different Origin you can use in your assignment rules.
For example, for emails to 'support@abc.com', make the Case Origin as "Email - Support". Then in case assignment rules, add a rule where if Case Origin is "Email - Support", assign to a defined support queue.