Email collector question

OK that’s great information @goran.metlic - thanks!
I had written a message here:

Goran’s suggestions got me one step further. Now a 3rd-party indeed is being created and attached to the project that is also created. However, the 3rd party has the wrong name and wrong contact (the address of the sender, which is wrong in my case, because I am forwarding relevant emails to my crm address that is scanned by dolibarr, as described in my post linked above. What I instead want to do is to supply the contact email adress manually in the subject line of every mail I forward to dolibarr.)
Does anybody know if there are similar tags as the one described, but now for the automatic creation of 3rd parties?