The Syncfusion native Blazor components library offers 70+ UI and Data Viz web controls that are responsive and lightweight for building modern web apps.
.NET PDF framework is a high-performance and comprehensive library used to create, read, merge, split, secure, edit, view, and review PDF files in C#/VB.NET.
Using Windows 10 with VS2017 ... PDFDocumentView and PDFViewer v16.4460.0.42 are both not able to view the annotations in the sample file attached (which was created using one of your sample applications.