Hello Ermano,
Greetings from Syncfusion support.
We are currently in the preview version of our Blazor components. Currently we haven‘t supported Data Manager in Blazor, so we were unable to achieve the remote data source support in it. We are currently working on implementing this feature in our end and it is scheduled to be released in our upcoming 2019 Essential studio Volume 2 main release which is scheduled to be rolled out by the month of June. Meanwhile, you can now track the current status of the feature, review the proposed resolution timeline, and contact us for any further inquiries through this link:
https://www.syncfusion.com/feedback/5811/
Regards,
Prince