Assign Ticket to site based on To Address

Assign Ticket to site based on To Address

We have created alias email addresses to send to for different sites. We create a lot of the tickets from our MSP email addresses. Is it possible to send an email from our MSP email to abc@ourhelpdesk.com and have it assigned to the ABC site? Then send an email to DEF@ourhelpdesk.com from the same MSP Email address and have it created in the DEF site?
This email would be coming from our MSPemail@ourhelpdesk.com email address.

Right now it looks like the ticket is created under our MSP site.

Thanks,
Steve