Hi Chloroplaste,
As far as I know, the display name in Outlook Address Book and Skype are controlled by the Display Name field in Active Directory:

Generally, it is not feasible for an end user to change the display name from Outlook user interface. Only your Exchange administrator can make this change from EAC or Active Directory. See the "Note" section in the following link:
Change the display name that e-mail recipients see
Hope the above information can be helpful.
Regards,
Yuki Sun
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