It is indeed a Crazy one but sometimes it helps much to pronounce a name in the right way. For example, My Name is Radhakrishnan but when Non-Indians try to pronounce it, definitely they struggle a bit. That is why it is good to have a spoken name setup in outlook so that they can simply listen to your voice before interacting with you. Okay. Let’s Begin.
First, you need to record your name clearly in .WMA Format. You can use Windows 10 Builtin Feature Voice Recorder.
By Default, It will be saved in the .m4a format. you can use Online Converter to convert from .m4a to .mwa which is required to set the Spoken Name.
Once you have the mwa file, Connect to Exchange PowerShell( Applies to Exchange Online and Exchange On-Premises) using the command.
If you trying for Exchange Online run the following command, In case, you are Exchange On-premises, Just open Exchange Powershell
Connect-EXOPSSession Run the below command to set the SpokenName.
Import-RecipientDataProperty -Identity “radhakrishnan.govindan@windowstechpro.com” -SpokenName -FileData ([Byte[]]$(Get-Content -Path “C:\Users\radhakrishnan\Desktop\1.wma” -Encoding Byte -ReadCount 0)) 
All Set, Now run the below command to validate,
Get-Mailbox radhakrishnan.govindan@windowstechpro.com|select HasSpokenName 
HasSpokenName is TRUE which means it has been set well. Now let’s give it some time to replicate. After some time, you will see the Audio Icon appears after your name. You can click on it to Hear the Name.
Let me know you come across any issues.. Thank you!!