Hi igibason,
I did a test with my outlook 2016 client, when I schedule the skype meeting, it looks like below:

You can use Exchange Transport rules to find and replace this identifier with whatever you want. For details, please refer to
https://technet.microsoft.com/en-us/library/gg398638.aspx
https://hanytaha.wordpress.com/2012/01/11/how-to-add-custom-text-to-lync-meeting-invitation/
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please
make sure that you completely understand the risk before retrieving any suggestions from the above link.
Regards,
Alice Wang
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