Hello,
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Normally, the Windows Runtime APIs are available in winui3 and Windows App SDK.
According to the Doc: ESim Class
This functionality is available only to mobile operator apps and UWP apps given privileged access by mobile network operators.
As far as I'm concerned, first of all, you need to get the privileged access from mobile network operators. If you have permission to use these APIs, you could try to use Windows App SDK and WinUI3 to develop an ESim application.
Thank you.
Jeanine
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