Feature Code during a call / conference -> next extension/room

We use freepbx for content services.

Is there a way to set a feature key, that do the following?

customer speaks with extension 2000.
The customer press “" or “5” or something else and will be transfered to extension 2001
customer speaks with extension 2001.
The customer press "
” or “5” or something else and will be transfered to extension 2002
customer speaks with extension 2002



Or the same in a conference room? -> room +1 with a feature code.

If someone is able to include that (if not already included in freepbx), we will pay for this feature (contact info [a"t] internet-group.net)

are you saying that while the customer is speaking to someone, you want to give the customer the ability to go to another extension? please explain more about what you are trying to do?