Hi @Jason VonD ,
Welcome to Microsoft Q&A!
Is this what you want? If so, you don't need to create two mail contacts in different languages, you can enter the English name in first name and the Japanese name in last name. Since my environment is set to English, I don't know how to use Japanese, so the Japanese name in the example is entered by pasting, you can copy the Japanese name you want to create into Notepad in advance for use.
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