Ok, thanks for your answer. All possibilities on that page based on from-address.
Are there any plannings to use subject instead of from-address (like in otrs or other ticket systems)?
Or am i able to change that on my own with a plugin? Or do i have to change that behavior in some core systems?
Actually i am not able to use mail interaction, because in our company i'm not allowed to create catch_all adresses. And the '+'-sign-trick doesn't work in our environment.

It would be great if i've any change to make it work.

Best regards
Axel

There are no plans to parse subjects, and I think such a feature would be at odds with other subject altering feature requests.

You can fork / patch / build your own MailAdapter, but we won't be able to provide you with assistance on such. It's just to large a drain on time and resources (we're 2 people). If you have professional level need, we do offer custom Consulting services.

Ok, thanks for your Help.

I created a little patch:
src/applications/transactions/editor/PhabricatorApplicationTransactionEditor.php : 2333

$body->addTextSection(
        pht('REPLY TO'),
        $target->getReplyTo());

    $target->setReplyTo(PhabricatorEnv::getEnvConfig('metamta.default-address'));

My mail-script (gets mail from pop3 and pushes it to mail_handler) rewrite the to-address to the reply-to address from body-text :-)

Quick and dirty. Have to clean up a little bit. It's dirty, but it works for me :-)

Best regards,
Axel