Hello @PetrS ,
Thanks for reaching out.
Can you provide some examples that will assist me in better understanding your case and end goals? If I understand correctly, you wish to create multiple Enterprise applications with the same Entity ID in Azure AD but with different Sign on URLs.
Azure AD Identifier (Entity ID) value much be unique across all applications in your AAD tenant. In case of configuring more than one instance, then you could consider using any of below format which basically adding a string after actual identity by this way they become unique across in your Azure AD tenant.
Examples:
Azure AD also support adding a string after the GUID as Entity ID, something like this GUID_AppName , once successful authentication then you would see same value as audience in token claim as shown below:
Hope this helps.
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