PADS Logic is not designed for this.
It may be possible somehow but I guess you need to tweak things in order to be able to do it so I will not recommend it.
I guess xDx-Designer can do this by default but I am not sure since I don't use it.
A workaround could be to have the two PCBs in a single .pcb file.
I have done this in the past and it works ok if the two PCBs always will be used in pairs.
Thank you for your answer.