Hi @Chrono Phan ,
Thank you for posting in this community.
You can not add a local resource link softwarecenter: in sharepoint directly.
As a workaround. If you wish to get link of some local, convert it in a network storage/file. create a shortcut of network location and add the shortcut link to a document library.
During my testing, The local link to the Software Center is placed in a jumpable html page. It is then uploaded to the SharePoint Document library. click on Open with app to jump from sharepoint to the Microsoft Software Center application hyperlink.
Hope this can help you.
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