Question Set Sieve filter before mail forwarding

[RaHa]

How do I set a Sieve filter that works before the mail is distributed to the mailboxes?

I have email addresses with redirects to other mailboxes. I want to set a filter that works before the mail is distributed to the other mailboxes.

The mail should be deleted or moved before it comes to the distribution of the forwarding.

How can I realize that?

Thank you!