I would like to as about specific configuration.

I have few domains eg:

domain1.com

domain2.com

domain3.com

domain1.com is my primary domain and contain eg. contact@domain1.com email address.

I would like set few aliases on domani2.com and domain3.com and redirect messages to contact@domain1.com.

Then i would like to reply to messages which are from @domani2.com sinding them by domain2.com alias (email which came from). 

Eg: I recieved email to testing@domain2.com`. Message was redirected to contact@domain1.com`. I want to reply from conatact@domani1.com` but as user testing@domani2.com`.

I don't know is that clear. If no, I'm sorry.

Ps. Gmail has sth similar and it called "Send messages as..."