Hello,
There's no known or supported method in Windows 11 to specify an alternate “phonetic” version of your computer's Bluetooth device name for use during connections. In other words, Windows will advertise the device name you've set (such as "device-name") as-is, and it’s up to the connecting device (or its operating system/TTS system) to decide whether to spell the name out or pronounce it.
For example, when your headphones connect to your Windows computer, they may spell out the name character by character if they assume that the string is an identifier rather than a word. On the other hand, a phone like your Galaxy S8 might simply pronounce the name as if it were a word.
There isn’t a built-in setting or registry tweak that lets you assign a separate “spoken” alias for Bluetooth handshakes on Windows. Your options are essentially limited to changing the device name to one that naturally leads to the desired pronunciation. Other than that, the behavior is dictated by the implementation in the connected device’s audio or TTS system.
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