Well, PdfSaveOptions class is there in the APIs. Could you tell us which Aspose.Cells.Dll (from which folder) you are using in your project. For normal .NET versions, make sure you are using the library from any of the following folders under “\lib” directory (when you install from Nuget repos.:
We were able to observe this issue as per your description and found some of the APIs are missing. We have recorded this issue in our database for further investigation and for a fix. Once, the issue is resolved or we have some other news for you, we will update you asap.
This issue has been logged as
CELLSNET-46041 - Some APIs like PdfSaveOptions and Auto Fit Rows and Columns methods are missing in .NET Core build
Your issue has been closed as Resolved but version number is not mentioned so it automatically means next version i.e. 18.5. But it is quite possible that 18.4 already contains it. But we recommend you to wait for 18.5.